Passive vs. Active EMS Air Filtration: Delivering the #1 Safety Feature Crews Demand

Passive vs. Active EMS Air Filtration: Delivering the #1 Safety Feature Crews Demand When evaluating fleet upgrades, EMS directors and fleet managers have a lot to consider. Budgets matter, but so does the environment where crews work and patients receive care. Research indicates that HVAC and air filtration rank highly among the safety features EMS professionals consider when evaluating a vehicle. Customer Insight: According to double-blind market research conducted by Smart Advantage, 76% of EMS professionals rank HVAC and air filtration as the #1 safety feature they look for in a vehicle. Crews may have concerns about airborne pathogens or patient modules that retain odors from previous calls. Department leaders also have to think about how illness and potential cross-contamination could affect staffing and vehicle availability. As departments write RFPs and plan their next fleet cycle, air management technology deserves a closer look. This guide breaks down the difference between passive filtration and active EMS vehicle air treatment. It also explains how HVAC design can support air quality, infection-control practices, crew comfort, and practical fleet maintenance. The Baseline: Understanding Passive HEPA Filters Standard passive filters are a common starting point in mobile healthcare, but it is important to understand what they do and what they do not do. A passive filter works much like a household vacuum bag. As air passes through the filter, physical dust, dirt, and particulates are captured in synthetic or paper filter media. The filter captures those particles rather than actively treating the circulating air. Over time, especially in a high-volume 911 environment, that filter media can accumulate material and require service or replacement. As material builds up, airflow may become restricted, and filtration alone may not address lingering odors after certain transports. This is where active air treatment adds another layer to the air-management strategy. Rather than replacing appropriate filtration, cleaning, and infection-control practices, an active system is designed to work alongside them to support a cleaner and more comfortable environment for crews and patients. Have a question for the team? Ask a Question What Is the Difference Between Active and Passive EMS Air Filtration? Passive filters use physical filter media, including HEPA filtration, to capture airborne dust and particulates as air passes through them. Active systems add technologies such as UV light and ionization that are designed to help reduce certain airborne contaminants and lingering odors as air circulates through the system. The basic difference is straightforward. Passive filtration captures contaminants in filter media. Active EMS vehicle air treatment processes circulating air. Used together, these approaches can support a department’s broader filtration, sanitation, and infection-control strategy. How Does the Dometic BreatheEasy Ionizer Work in an Emergency Vehicle? The Dometic BreatheEasy system uses an active photocatalytic purification process. Instead of relying on passive filtration alone, it pairs UV light with nano-filters. As air cycles through the system, the technology is designed to help reduce airborne contaminants, odors, and particulates while providing ongoing air treatment when the system is operating. Frazer integrates Dometic BreatheEasy technology into the module’s climate-control system and also uses this foundational technology in specialized infectious disease units. The goal is practical: help maintain fresher air and reduce the buildup of biological matter associated with unpleasant odors. High-Volume HVAC: The Engineering Behind 2-Minute Recirculation It is fair for fleet maintenance leaders to ask how much benefit UV technology can provide inside a mobile environment. Air-treatment performance depends in part on moving air through the system, which makes HVAC design and airflow an important part of the equation. Frazer addresses this with a dedicated 15,000 BTU self-contained climate unit, an independent exhaust blower, and a custom plenum setup. This high-capacity HVAC configuration is designed to recirculate the air in the treatment compartment every two minutes, providing repeated opportunities for circulating air to move through the treatment process. The system is also designed to handle significant environmental changes while supporting the module’s structural seal. It delivers a minimum cooling differential of 25 to 30 degrees and can maintain a 35°F+ differential between outside and inside temperatures. That climate-control capacity supports the operating environment for crews, patients, internal electronics, and climate-sensitive medical cargo while maintaining the module’s air-management cycle. How Can EMS Vehicle Design Help Reduce Cross-Contamination Between the Module and Cab? Physical separation can help reduce opportunities for air exchange between vehicle compartments. Frazer approaches this with a chassis-independent 115VAC HVAC system for the patient module. Because the module does not rely on shared HVAC ducting with the driver’s cab, its air handling remains separate from the front-seat climate system. Chassis-Independent Air Management Department leaders also have to consider the staffing and operational effects of crew illness. When someone is out sick, schedules can get tighter and available personnel can be stretched even further. Vehicle design cannot replace proper infection-control procedures, but it can support the department’s broader approach. Some emergency vehicle configurations rely on chassis systems for portions of their climate-control needs. Frazer takes a different approach. The module’s 115VAC air-conditioning system operates from an independent power source, such as an onboard generator or MEPS system, rather than relying on the truck’s engine-driven air-conditioning system. Keeping the HVAC systems separate helps limit direct air exchange through shared climate-control ducting between the patient module and driver’s cab. This physical separation is designed to reduce opportunities for cross-contamination through shared HVAC pathways while supporting the department’s broader infection-control practices. Advanced Air Treatment Designed for Field Serviceability Air treatment is only useful if departments can keep it working. Fleet managers and mechanics need to consider how additional vehicle systems affect maintenance, downtime, and long-term ownership. Specialized equipment can add service requirements, so Frazer designs its electrical and air-treatment systems with field serviceability in mind. Frazer’s electrical design follows the KISS principle: Keep It Super Simple. We use standard point-to-point wiring, common terminal strips, and standard automotive relays, reducing reliance on proprietary printed circuit boards in these applications. The same practical thinking applies to routine HVAC and purification maintenance. Physical air filters, Part No. 35901, and active

Protecting Your Mobile Stroke Unit Investment: Support After the Sale

Protecting Your Mobile Stroke Unit Investment: Support After the Sale Investing in a Mobile Stroke Unit (MSU) is a major step in bringing stroke care closer to the patient. Instead of relying only on traditional “door-to-needle” treatment, an MSU can help medical teams begin critical care in the field. That capability comes with a significant investment. When an MSU can approach $1 million, it makes sense for hospital boards, city leaders, and procurement teams to pay close attention to the purchase price. But the initial price is only part of the cost. Downtime, maintenance, serviceability, and the useful life of the vehicle can all affect what an MSU costs to operate over time. This guide explains what EMS directors and healthcare administrators should consider when looking beyond the initial purchase price. We’ll cover independent power, serviceability, post-sale support, maintenance, and remounting so you can make a more informed decision about your MSU investment. The True Cost of a Mobile Stroke Unit: Looking Beyond Initial Cost When organizations compare bids for a new Mobile Stroke Unit, the initial capital expense naturally gets a lot of attention. Staying within budget matters, but the purchase price does not tell you what the vehicle may cost to operate over the next 10 or 20 years. A common concern from buyers is simple: “The initial cost of an MSU is too high to justify to our board.” That is a fair question. One way to look at it is through Lowest Overall Cost of Ownership, or LOCO. This approach considers more than the price on the purchase order. It also looks at maintenance, downtime, service needs, and eventual replacement costs. A lower purchase price does not always mean a lower long-term cost. The real question is what the MSU will require throughout its service life. Depending on how the vehicle is configured, maintained, and operated, spending more upfront may help reduce costs later. Have a question for the team? Ask a Question Engineering for Uptime: The Role of Chassis-Independent Power Fleet managers and medical directors should ask an important question before choosing an MSU: “What happens to our clinical environment if the truck engine goes down?” Some emergency vehicle designs depend on the truck chassis for parts of the module’s electrical and climate-control systems. Depending on the design and the type of chassis failure, an engine or electrical problem may affect systems inside the clinical space. That matters when the module contains temperature-sensitive medical equipment, a CT scanner, and other systems that need reliable electrical power. Frazer designs Mobile Stroke Units with chassis-independent power options. Depending on the configuration, systems such as a Cummins Onan generator, MEPS, or Harrison hPower can provide a dedicated source of power for the clinical module. What does that mean in the field? Depending on the type of chassis issue and the unit’s configuration, the independent power system is designed to support continued operation of module systems. That can include 120V AC power, climate control, air purification, and other onboard equipment used by the medical team. Powering and Securing the Onboard CT Scanner Putting a CT scanner inside a moving vehicle takes more than finding enough room. The scanner’s weight and power requirements call for a purpose-built structural and electrical system. Frazer uses a fixed mounting system for the Siemens SOMATOM On.site scanner. This removes the need for floor rails and supports image acquisition on vehicle inclines of up to 5 degrees. Frazer also developed an SAE J3043-compliant CT scanner mount in the U.S. and voluntarily tested the retention system beyond 50,000 pounds of force without structural failure. The system is designed to help retain the scanner during a collision and reduce the potential for movement inside the patient compartment. The Operational Cost of Downtime What is the true cost of EMS vehicle downtime? The cost of downtime goes beyond the repair bill. When a Mobile Stroke Unit is unavailable, it may affect opportunities to provide on-scene stroke care, vehicle availability, transport operations, and the department’s ability to cover calls with reserve units. Modern emergency vehicles can use complex electrical systems that require specialized software, diagnostic tools, parts, or technical support. Depending on the system and the problem, that can affect how quickly a local fleet team can find the issue and complete the repair. Frazer takes a simpler approach to electrical design. Instead of relying only on proprietary printed circuit boards, Frazer units use point-to-point wiring, common terminal strips, and standard automotive relays. Why does that matter? The goal is straightforward serviceability. Fleet personnel can access and troubleshoot many electrical components using familiar methods and commonly available parts. When applicable, that can make diagnosis and repair easier and help teams get the unit back into service. Why Support After the Sale Matters Why is post-delivery support important for a Mobile Stroke Unit? A Mobile Stroke Unit is a complex, high-value asset. Access to technical help, warranty support, parts, and planned maintenance can make a meaningful difference when service is needed. Every organization weighs price, warranty coverage, serviceability, and post-delivery support differently. Research can also help show what EMS and fire professionals value when choosing a vehicle provider. According to an independent, double-blind industry survey of 100 EMS and fire professionals, fewer than 25% of respondents named price as their top driver when selecting a builder. When respondents rated individual attributes, support after the sale ranked as their top priority. At Frazer, that support is part of the Frazer Family Experience. When customers need technical help, they can connect with Frazer employees who know our vehicles and systems. Frazer also provides warranty coverage that includes a 5-year warranty on module paint and electrical wiring. In that same independent survey, 39% of respondents identified Frazer as the brand that spends the least amount of time in the shop. The result reflects the responses of the professionals included in that study and gives organizations another data point to consider when evaluating serviceability and post-sale support. Proactive Maintenance for a High-Value Asset

How to Start a Mobile Stroke Unit Program: The 5-Pillar Logistical Roadmap

How to Start a Mobile Stroke Unit Program: The 5-Pillar Logistical Roadmap Securing funding for a Mobile Stroke Unit can be a major milestone. Turning that funding into an operational program is a different challenge. Hospital administrators and medical specialists have to consider more than the clinical side of stroke care. An MSU brings together departments that may not normally work side by side, including EMS, IT, Radiology, fleet operations, clinical leadership, and hospital administration. Each team brings its own requirements, and those requirements need to work together inside one highly specialized mobile healthcare unit. This guide focuses on that operational challenge. We have organized the process into five practical pillars to help your team ask the right questions, involve the right people, and plan for what happens after your MSU enters service. Pillar 1: Bring the Right Teams Together Early An important first step is getting the departments involved in the MSU program into the same conversation. Radiology may be thinking about the CT scanner and radiation requirements. IT may be focused on secure connectivity and telemedicine. EMS Operations may be thinking about vehicle size, weight, drivability, maintenance, and dispatch. None of these concerns exists on its own. Bringing stakeholders together early gives your team a chance to identify competing requirements and solve problems before the vehicle specification is finalized. Align Radiology and IT IT and Telemedicine teams should be part of the planning process early. An MSU is a mobile clinical environment, so secure and reliable data transmission needs to be considered alongside the physical vehicle design. Your team should determine how remote neurologists will communicate with the onboard crew and how the system will support your selected telemedicine platform. Radiology also needs a seat at the table. Integrating a CT scanner affects the layout, weight, power requirements, and other elements of the unit. For example, the Siemens SOMATOM On.site portable head CT scanner uses internally lead-lined gantry covers and radiation shields at the front and back bore openings. Understanding requirements like these early helps the vehicle team design around the medical equipment instead of trying to accommodate it later. Include EMS and Fleet Operations Your municipal or contracted EMS fleet team may ultimately be responsible for driving requirements, chassis maintenance, and routine vehicle service. Involving them early creates an opportunity to talk about weight, drivability, maintenance access, and how the vehicle will fit into the existing fleet. Frazer uses a KISS Principle, or “Keep It Super Simple,” approach to electrical architecture. Point-to-point wiring and standard automotive relays are designed to make many module components easier for local fleet mechanics to service without proprietary computer diagnostics. For an MSU program, easier access to service can matter because the vehicle only helps patients when it is available and ready to respond. Pillar 2: Plan the Real-World Workflow and 911 Integration A Mobile Stroke Unit can have advanced clinical capabilities, but your team still needs a clear plan for getting it to the right patient. Before go-live, program leaders should define how the MSU fits into local 911 response, how crews will interact with municipal EMS resources, and what happens after the initial patient assessment. Build a Dispatch Strategy One approach is concurrent dispatch. When a 911 call center identifies a potential stroke based on established screening criteria, dispatch can send both a standard EMS unit and the MSU. The first arriving crew can begin assessment and triage according to the program’s protocols while the MSU responds. The right approach depends on your local EMS system, geography, clinical protocols, and available resources. The important part is deciding how the MSU will fit into the system before the program launches. Have a question for the team? Ask a Question Plan the Patient’s Next Step An MSU program may be designed to reduce the time between patient contact, diagnostic imaging, and appropriate treatment. An onboard team can include a critical care nurse, CT technologist, paramedic, and remote neurologist who work together to assess and scan the patient near the point of contact. If the clinical team confirms an ischemic stroke and the patient meets the program’s treatment criteria, medications such as TPA or TNK may be administered in the field under established clinical protocols. From there, the patient’s condition, local protocols, and receiving hospital capabilities can help determine the appropriate destination and next level of care. Pillar 3: Plan for Power and Climate Control A Mobile Stroke Unit carries sensitive medical and communications technology into an environment that moves, vibrates, and operates in changing weather conditions. That makes reliable power and climate control important parts of the vehicle design. Why Independent Power Matters A CT scanner, telemedicine equipment, and heavy-duty air conditioning can require substantial electrical power. Trying to support those loads through the chassis electrical system introduces questions about voltage demand, battery capacity, and equipment performance. Frazer addresses these needs with independent power systems. Depending on the configuration, the module can use a dedicated 120V AC power source such as a Cummins Onan generator or MEPS system. Because module power is independent from the chassis electrical system, critical module systems can operate without depending on the truck engine, subject to the requirements and condition of the installed equipment. Protect the Environment Around Your Equipment Temperature and humidity matter when you are carrying sensitive medical technology. Frazer uses a self-contained 120V AC air conditioning system designed for the operating environment of emergency medical vehicles. The system is designed to maintain a minimum cooling differential of 25 to 30 degrees under applicable operating conditions. That cooling capacity helps manage patient-compartment temperatures in hot environments while supporting the environmental needs of onboard medical equipment. Pillar 4: Ask for the Safety Data Heavy medical equipment inside a moving vehicle deserves careful attention. Hospital Risk Management, Legal, clinical leaders, and fleet teams should understand how equipment is mounted and what testing supports the design. Securing the CT Scanner Frazer developed an SAE J3043-compliant CT scanner mounting system for its Mobile Stroke Units. The specialized retention

Mobile Stroke Unit Staffing: Coordinating Nurses, Techs, and EMS

Mobile Stroke Unit Staffing: Coordinating Nurses, Techs, and EMS You have secured the budget, reviewed the clinical data, and set the goals for your new Mobile Stroke Unit (MSU) program. Now it is time to turn that plan into a working program. That often brings up an important question from local EMS partners: “Are our medics expected to run the CT scanner?” It is a fair question. A Mobile Stroke Unit brings a specialized medical team and hospital imaging equipment into a moving vehicle. That changes the workspace and can raise questions about responsibilities, scope of practice, safety, and how everyone will work together. The good news is that your paramedics do not have to become CT experts. With clearly defined roles and a purpose-built workspace, each member of the MSU team can focus on the job they are trained to do. Here is how a common MSU staffing model works and what it can mean for your EMS partners. Why Paramedics May Have Questions About Mobile Stroke Units When an EMS chief or frontline paramedic first hears about a Mobile Stroke Unit, questions are natural. Most emergency vehicles are designed around smaller crews. Add a CT scanner and several clinical specialists, and the normal workflow changes. One concern may be “scope creep.” Paramedics are trained to manage emergency scenes, provide patient care, and support safe transport. They may wonder whether adding a mobile CT scanner means they will also be expected to operate unfamiliar hospital equipment, troubleshoot the scanner, or take on new clinical responsibilities. Clear roles can help address those concerns before the unit ever goes into service. In a purpose-built MSU, the paramedic can remain focused on EMS responsibilities while other members of the clinical team manage imaging, advanced treatment, and neurological evaluation according to the program’s protocols. What Does a Mobile Stroke Unit Staffing Model Look Like? A Mobile Stroke Unit may include a certified CT Technologist, a Critical Care or Neuro Nurse, a Paramedic or EMT, and a Vascular Neurologist who can connect remotely through telemedicine. Exact staffing varies by program, local requirements, and clinical protocols, but the goal is the same: give each specialist a clear role and create a team that can work together efficiently. Clear responsibilities matter because an MSU is not simply an emergency vehicle with a CT scanner added to it. It is a mobile clinical environment. The people, technology, power systems, communications, and workspace all need to support the program’s care model. The Certified CT Technologist: Imaging Expert The CT Technologist handles the imaging side of the operation. This can include positioning the patient, operating the CT scanner, acquiring the required scans, and supporting secure transmission of those images to the hospital network based on the program’s procedures. This role keeps specialized imaging equipment in the hands of a trained imaging professional instead of shifting that responsibility to the EMS crew. The Critical Care or Neuro Nurse: Treatment Expert The Critical Care or Neuro Nurse focuses on advanced patient care inside the module. Depending on the program’s protocols and applicable scope-of-practice requirements, this may include patient assessment, IV access, and administering medications ordered by the neurologist, including thrombolytics such as tPA or TNK and medications used to manage blood pressure. The Paramedic or EMT: Scene and Transport Expert The Paramedic or EMT remains an important part of the MSU team. Often provided by the partner EMS agency, this role can include communication with 911 dispatch, scene safety, EMS patient care, assistance with patient loading, and operation of the vehicle. In this model, the EMS professional does not need to become the CT expert. The paramedic or EMT can stay focused on the emergency response and transport responsibilities defined by the program. The Vascular Neurologist: Diagnostic Expert Some programs may have a neurologist onboard during launch and later move to remote support. With the MSU’s telemedicine system, the neurologist can assess the patient, review available imaging, and make diagnostic and treatment decisions based on the program’s clinical protocols. Who Operates the CT Scanner on a Mobile Stroke Unit? In the staffing model described here, a certified CT Technologist operates the CT scanner. The paramedic or EMT can stay focused on EMS patient care, scene safety, and transport instead of taking responsibility for specialized hospital imaging equipment. Putting that distinction into your standard operating procedures can also help answer questions from agency leaders, unions, and frontline crews before the program launches. Everyone should know who is responsible for the scanner, who provides treatment, who manages the scene, and who makes clinical decisions. Clear expectations make it easier for the team to work together. Have a question for the team? Ask a Question Is There Enough Room for the MSU Team? Space matters. An MSU needs room for the CT Technologist, nurse, and EMS professional to perform their jobs without constantly working around one another. That is why the interior layout should be considered early in the program design process rather than after the clinical equipment has already been selected. Designing Around Space and Workflow A conventional emergency vehicle layout may not provide the space needed for a mobile stroke team and its specialized equipment. Frazer designs MSUs with wide aisle space to support movement through the patient compartment and give team members practical working areas. The CT scanner itself also affects the layout. For example, the Siemens SOMATOM On.site uses a telescopic gantry. During a scan, the gantry moves over the patient while the external base remains stationary. Frazer’s fixed mounting approach eliminates the need for floor rails. That can remove potential trip points and areas where dirt can collect while keeping more of the floor clear for the clinical team. The goal is simple: design the workspace around the people who will use it every day. How Is the CT Scanner Secured? A CT scanner is a large, heavy piece of medical equipment. Putting one inside a moving vehicle makes equipment retention an important part of the MSU design.

Maximizing the Golden Hour: Why AHA Mobile Stroke Unit Guidelines Matter

Maximizing the Golden Hour: Why AHA Mobile Stroke Unit Guidelines Matter A Mobile Stroke Unit (MSU) is a specialized mobile healthcare unit equipped with technology such as a portable CT scanner, telemedicine capabilities, and medications used to treat eligible stroke patients. AHA guidance addressing mobile stroke care reflects the growing role MSUs can play in evaluating and treating stroke before a patient reaches the hospital. With the right clinical team and equipment on board, an MSU can help diagnose acute ischemic stroke and begin treatment at or near the patient’s location. By bringing diagnostic and treatment capabilities into the field, MSU programs are designed to reduce onset-to-needle time. Research cited in this article has shown reductions of up to 41 minutes, giving clinical teams more time to act when every minute matters. In acute ischemic stroke care, time can have serious clinical consequences. Research estimates that every minute treatment is delayed is associated with the loss of approximately 1.9 million neurons. For decades, emergency response has focused on getting patients to the hospital quickly and reducing the “door-to-needle” interval. Traffic, triage, imaging, and other steps at the emergency department (ED), however, can add time before treatment begins. Today, some stroke program directors and neurology teams are looking beyond “door-to-needle” time. Their focus is increasingly on “onset-to-needle” time and how certain emergency department capabilities can be brought closer to the patient. Clinical research has helped establish mobile stroke programs as an evidence-supported approach to prehospital stroke care. Turning that clinical model into a working vehicle presents another challenge. It requires thoughtful mechanical and electrical engineering built around the needs of the clinical team. This guide looks at the clinical case for Mobile Stroke Units and several important design considerations for supporting stroke care in the field. The Clinical Reality: Redefining “Onset-to-Needle” Time A key goal in acute ischemic stroke care is to administer thrombolytic treatment, such as tissue plasminogen activator (tPA), to eligible patients as quickly as clinically appropriate. The “golden hour” refers to the critical first 60 minutes after symptoms begin. Historically, traditional emergency medical services (EMS) models have struggled to deliver treatment within this window, with fewer than 5% of patients receiving treatment during that first hour. An MSU brings key capabilities closer to the patient. A specialized team can perform a CT scan and consult with a neurologist before the patient reaches the hospital. According to scoping reviews of MSU effectiveness, this approach can reduce median onset-to-needle times by 20 to 41 minutes. Some programs have also reported that up to 33% of their MSU patients receive treatment within the first 60 minutes. Research has also associated faster treatment through mobile stroke programs with improved 90-day modified Rankin Scale (mRS) outcomes. Available data suggests that patients treated sooner through these programs may be more likely to experience minimal to no long-term disability. Have a question for the team? Ask a Question Bringing the ED to the Driveway: AHA Guidance and Mobile Stroke Care Starting a mobile stroke program is a significant investment. Hospital boards and leadership teams need strong clinical evidence before committing the people, equipment, and resources required to make a program successful. A growing body of clinical research and professional guidance now supports consideration of MSUs as part of prehospital stroke systems of care. AHA guidance addressing Mobile Stroke Units reflects the growing clinical evidence surrounding prehospital stroke diagnosis and treatment. Instead of serving only as transportation, an MSU can provide a specialized mobile healthcare environment for imaging, neurological consultation, and treatment before hospital arrival. Frazer has been involved in Mobile Stroke Unit development since the early years of deployment in the United States. Frazer built the nation’s first Mobile Stroke Unit in 2014 and five of the first seven MSUs deployed in the country. The clinical mission defines what the team needs to accomplish. Our job is to engineer a mobile environment that supports that mission in day-to-day field operations. Powering the Mission: Supporting the CT Scanner Electrical power is an important consideration for fleet managers, mechanics, and clinical teams evaluating an MSU. A 32-slice SOMATOM On.site portable CT scanner, combined with a 5G telemedicine array and standard medical equipment, can require a substantial amount of clean, consistent electricity. How Does a Mobile Stroke Unit Power a CT Scanner? Using a standard truck alternator as the primary power source for advanced medical imaging can put additional demand on the chassis electrical system. Frazer uses an independent 120V AC generator as the primary power source for the module. This configuration provides dedicated power for equipment such as the SOMATOM On.site CT scanner and telemedicine system while reducing reliance on the chassis batteries. In the field, this independent power architecture is designed to reduce the risk of voltage drops affecting medical equipment. When an MSU depends only on the chassis electrical system, changes in voltage while idling may affect CT scanner operation. Separating module power from the truck’s primary electrical system provides a dedicated source for medical equipment during field operations. Frazer also incorporates a 12V DC backup system to provide another layer of electrical redundancy if the primary generator has an issue. Protecting the Payload: Climate Control and Structural Safety Putting sensitive, heavy medical equipment inside a moving vehicle creates unique engineering and operational challenges. Two important considerations are how that equipment is secured and how the clinical environment is maintained. Is the CT Scanner Secured for Emergency Vehicle Operation? A CT scanner weighing approximately 1,000 pounds needs a mounting system engineered for the forces that can occur during vehicle operation and a collision. Frazer’s CT scanner mounting system is tested for compliance with SAE J3043. The standard requires the system to withstand forces associated with a 26 G collision, and Frazer’s mount was successfully tested with more than 50,000 pounds of force. This testing gives hospitals and clinical teams documented information about the performance of the mounting system. Frazer designs the structural frame specifically to secure the scanner and help reduce hazards associated with

“You Can’t Put a CT Scanner in a Mobile Unit.” How Frazer Engineered a First

“You Can’t Put a CT Scanner in a Mobile Unit.” How Frazer Engineered a First One of the biggest engineering challenges was putting a roughly 1,000-pound mobile CT scanner inside a moving emergency vehicle. Frazer developed an SAE J3043-compliant scanner mount and successfully tested the system with more than 50,000 pounds of force. The goal was simple: securely mount the scanner while supporting the safety of the people working around it. For hospitals developing a Mobile Stroke Unit program, the vehicle is only one part of the equation. A key clinical goal may be reducing “onset-to-needle” times by bringing parts of stroke assessment and treatment closer to the patient. Once a program moves forward, hospital leaders also have to answer a very practical question: How do you safely put hospital-grade imaging equipment into a vehicle and make it work in the field? That question affects everything from structural engineering and electrical power to equipment mounting, climate control, and crew safety. This article looks at how Frazer approached those challenges and how those lessons continue to shape our Mobile Stroke Unit projects today. 2014: Building the Nation’s First Mobile Stroke Unit Building a first-of-its-kind mobile healthcare program comes with plenty of unknowns. Hospitals have to bring clinical, technical, financial, and operational teams together around a vehicle that may need to perform jobs normally handled inside a hospital. Frazer’s Mobile Stroke Unit experience began in 2014, when we partnered with UTHealth to engineer and build the nation’s first Mobile Stroke Unit. Frazer later built five of the first seven MSUs in the United States. That work involved more than building the vehicle. Mobile CT integration can require coordination among hospital IT teams, radiology departments, telemedicine providers, vehicle engineers, and partner EMS agencies. Bringing those groups together early can help hospitals identify requirements before they become problems later in the project. Want to see more of Frazer’s experience in this space? Explore our Frazer Mobile Stroke Units. Securing a 1,000-Pound CT Scanner in a Moving Vehicle A CT scanner is a serious piece of equipment. At roughly 1,000 pounds, its weight and mounting requirements have to be considered as part of the vehicle’s overall design. The mounting system also has to account for the forces the vehicle and its equipment could experience during a collision. Frazer builds its modules using 6061 T-6 structural aluminum tubing, with no wood used in the framing. For a Mobile Stroke Unit, that structure becomes the foundation for integrating the scanner and the other systems needed to support it. The scanner itself also needs a mounting system designed for its weight and application. A mount intended for typical equipment may not be suited for a payload this heavy. How does SAE J3043 apply to Mobile Stroke Unit equipment? SAE J3043 addresses the securement of equipment in an emergency medical vehicle and includes requirements related to 26 G forces. With a mobile CT scanner weighing roughly 1,000 pounds, Frazer needed a mounting solution built for the application. Frazer engineered an SAE J3043-compliant CT Scanner Mounting & Retention System and successfully tested it with more than 50,000 pounds of force. That testing provides documented performance data for the mounting system under the tested conditions. It is one example of how we approach equipment integration in a Mobile Stroke Unit. Learn more about Frazer’s approach to safety and crash compliance standards. Managing Radiation, Power, and a Tight Workspace Putting imaging equipment inside a vehicle creates challenges you do not have in a traditional hospital room. Space is limited. Vehicle weight matters. The equipment needs dependable power and cooling. Clinical teams also have to consider radiation exposure and the working environment around the scanner. That means the CT scanner cannot be treated like another piece of equipment added after the vehicle is designed. The scanner, power system, HVAC, suspension, available payload, and interior layout all have to work together. Have a question for the team? Ask a Question How is radiation scatter managed in a Mobile Stroke Unit? Frazer integrates the SOMATOM On.site portable head CT scanner by Siemens Healthineers into its Mobile Stroke Unit design. As detailed in the Siemens Brochure, the scanner features a self-shielding radiation system. This includes internally lead-lined gantry covers and radiation shields on the front and back bore openings, which minimize scatter radiation to enhance safety for onboard staff. By relying on this integrated shielding, clinical staff can confidently capture vital 32-slice imaging right in the patient’s driveway. The SOMATOM On.site also features a first-of-its-kind telescopic gantry. Because the radiation source moves away from the patient during scanning while the base remains stationary, it simplifies patient positioning in the tight confines of a mobile unit and minimizes motion artifacts. Furthermore, the CARE 2D Camera allows technologists to maintain continuous visual contact with the patient from the touch interface, even when radiation shield covers are in place. Capturing high-quality diagnostic images also requires a stable platform. Vehicle position matters. Frazer uses a LiquidSpring™ suspension system with ride-control features and automatic leveling. When the vehicle is parked on an uneven or sloped surface, the system is designed to help provide an appropriate operating position for the imaging equipment, ensuring accurate calibration. Frazer’s fixed mounting enables reliable CT image acquisition even on vehicle inclines of up to 5°. How do you power a CT scanner in a Mobile Stroke Unit? Hospital-grade imaging equipment needs a power source that can support its electrical requirements. Frazer Mobile Stroke Units use a primary 120V AC generator that operates independently of the truck chassis. The system is designed to power the mobile CT scanner, telemedicine equipment, and dedicated HVAC without depending on the chassis alternator as the primary source for those module loads. This independent approach separates the module’s primary AC power needs from the chassis electrical system. It gives the specialized equipment inside the module its own source of power while the unit is in service. The same system supports the module’s HVAC. Medical imaging equipment produces heat and needs to

Pioneering the Mobile Stroke Unit: How Frazer Changed Prehospital Care

Pioneering the Mobile Stroke Unit: How Frazer Changed Prehospital Care During an acute ischemic stroke, every minute matters. Clinical research indicates that approximately 1.9 million neurons can be lost for every minute blood flow is not restored. For decades, stroke care focused heavily on the “door-to-needle” timeline: get the patient to the hospital, move through emergency department triage, complete CT imaging, and then determine whether clot-busting medication such as tPA can be administered. Mobile Stroke Units bring diagnostic and treatment capabilities closer to the patient. Clinical data indicates this approach can reduce treatment times and may improve outcomes while reducing long-term disability. But taking hospital-level stroke care into the field creates a major engineering challenge. How do you safely transport and power a roughly 1,000-pound hospital-grade CT scanner inside a moving emergency vehicle while supporting diagnostic quality and crew safety? In 2014, Frazer helped address that challenge by engineering a Mobile Stroke Unit from the ground up. Today, Mobile Stroke Units are moving beyond early clinical trials and becoming part of the stroke-care model in a growing number of communities. Here’s a closer look at the clinical history, safety considerations, power systems, and vehicle infrastructure behind a field-ready Mobile Stroke Unit. Have a question for the team? Ask a Question The Origin of the Mobile Stroke Unit: Pushing the Limits of Mobile Healthcare The idea behind the Mobile Stroke Unit is straightforward: reduce the time between the onset of a stroke and treatment by bringing critical diagnostic capabilities closer to the patient. In early 2014, Dr. James C. Grotta, then-director of stroke research at the Clinical Institute for Research & Innovation at Memorial Hermann-Texas Medical Center, introduced the idea of a specialized stroke vehicle to the UTHealth Development Board. After seeing a similar concept in Germany, Dr. Grotta recognized the potential impact of eliminating time normally spent transporting and moving a patient through the hospital before treatment could begin. Turning that idea into a working vehicle in the United States required specialized engineering and a willingness to rethink traditional emergency vehicle design. John and Janice Griffin, owners of Frazer, stepped forward to help fund and build the project. “Our company likes to push the limits and this had never been done before,” noted Laura Griffin, CEO and president of Frazer, during the launch of the unit. “Once everyone sees the possibility of putting a CT scanner in an emergency vehicle, the question is what else can we do?” The partnership between UTHealth, Memorial Hermann, and Frazer helped advance prehospital stroke care. By bringing CT imaging to the patient, Mobile Stroke Units can reduce reliance on standard hospital emergency department workflows before imaging and support field triage. Studies have shown that Mobile Stroke Units typically reduce onset-to-needle times by 20 to 41 minutes. They can also increase “golden hour” treatment rates, with tPA administered within the first 60 minutes after symptom onset, from less than 5% with standard transport to as high as 33%. Giving thrombolytics in the field requires clinicians to have the information needed to distinguish an ischemic stroke from a hemorrhagic stroke. That makes reliable mobile imaging a critical part of the care model. Diagnostic Imaging on the Go: The Siemens SOMATOM On.site When a neurologist evaluates a patient through telemedicine in the field, diagnostic imaging provides important information that can support treatment decisions. To help clinicians detect or rule out bleeding, Frazer integrates advanced imaging systems such as the Siemens SOMATOM On.site, a 32-slice portable head CT scanner designed for point-of-care neuroimaging. How do Mobile Stroke Units support diagnostic image quality? Mobile Stroke Units can support diagnostic image quality through specialized CT equipment and engineered vehicle mounting systems. Frazer integrates scanners such as the Siemens SOMATOM On.site, which uses a telescopic gantry that moves the radiation source while the base remains stationary. Paired with a fixed-mount design, the configuration is designed to reduce the effects of vehicle movement and support image acquisition on inclines up to 5°. Because the heavy rotating components move internally, the entire machine does not need to travel along floor rails during imaging. This approach can help reduce vibration-related movement that could affect imaging, giving specialists the information they need to evaluate the patient and determine an appropriate treatment plan in the field. How Do You Mount a CT Scanner in a Moving Emergency Vehicle? Clinical teams are focused on patient outcomes, but Risk Management and Fleet Operations have another important concern: keeping people and equipment secure inside the vehicle. A heavy, active CT scanner requires specialized engineering designed to retain the equipment during severe vehicle events. A roughly 1,000-pound piece of medical equipment can create significant forces during a major collision. Equipment retention therefore has to be considered alongside clinical capability when developing a Mobile Stroke Unit. What safety considerations apply when putting a CT scanner in an EMS vehicle? Integrating a CT scanner into an EMS vehicle requires mounting engineering appropriate for the equipment’s size and weight. Frazer developed an SAE J3043-compliant fixed-mounting system for the CT scanner and tested the retention system beyond 50,000 pounds of force to support crew and equipment protection during severe collisions. The mobile environment also requires measures designed to manage scatter radiation during image acquisition. Frazer’s Mobile Stroke Unit integration incorporates safety features such as the internally lead-lined gantry covers and front and back bore shields found on the Siemens SOMATOM On.site. A CARE 2D Camera and bore lighting allow the technologist to maintain visual contact with the patient through the touch interface, supporting patient monitoring while staff remain behind radiation shielding. Supporting the Golden Hour: Independent Power and High-Performance HVAC Advanced medical equipment needs vehicle infrastructure designed around its operating requirements. For clinical operations and fleet teams, two major considerations are electrical stability and temperature management. The power system needs to support the CT scanner and other equipment during emergency response, while the HVAC system needs to manage both outside temperatures and the heat generated by sensitive electronics. How do you power a

EMS Vehicle Air Circulation: How High-Capacity HVAC Supports Crews on Challenging Calls

EMS Vehicle Air Circulation: How High-Capacity HVAC Supports Crews on Challenging Calls Anyone who has worked in EMS knows how quickly the back of a unit can heat up on a summer afternoon. Add a difficult patient care situation, a long transport, or strong odors, and the environment inside the module can become another challenge for the crew. That is why EMS vehicle air circulation and cooling performance deserve attention when departments evaluate their next vehicle. Climate control also matters beyond crew comfort. Maintenance teams have to consider how the HVAC system is powered, how much the chassis must idle, and how quickly components can be serviced when something goes wrong. In double-blind industry research conducted by Smart Advantage, 76% of emergency vehicle procurement professionals ranked HVAC and air filtration as their top safety and cab-environment priority. Crash-test results were selected by 70%, while infection-control isolation was selected by 56%. So, what should an apparatus committee look for? This guide explains what 450 CFM airflow means, why HVAC performance can vary with some chassis-dependent systems, and which specifications can help departments compare their options. The Frontline Reality: Managing Challenging Calls in the Patient Compartment In some emergency vehicle configurations, crews may have to balance ventilation with cooling. An exhaust blower can remove air from the module, but replacement air coming from outside may be hot and humid. That creates another load for the HVAC system. If crews rely mostly on recirculation instead, strong odors may remain in the patient compartment longer. The goal is simple: keep air moving while maintaining a comfortable working temperature. Doing both requires enough airflow, cooling capacity, and power to support the system under real operating conditions. Heat, Odors, and the Clinical Working Environment Extreme heat and strong odors can add to the physical and sensory demands crews already face during patient care. Maintaining a more comfortable patient compartment gives crews one less environmental challenge to manage during difficult calls and extended shifts – especially when navigating demanding regional terrain and rural response corridors where travel times are extended. The 450 CFM Equation: What Airflow Means Inside the Module HVAC performance is about more than the temperature coming from a vent. Air also needs to move through the patient compartment. Looking at the module’s interior volume and the blower’s airflow rating provides a useful way to understand how frequently air can move through the system. How Often Should Air Circulate in an EMS Vehicle? Frequent air movement can help reduce stagnant air and lingering odors inside the patient compartment. Frazer’s 450 CFM circulation fan is designed to move an air volume comparable to a typical patient compartment through the system about every two minutes. The HVAC system is also designed to maintain up to a 35°F difference from the outside temperature under applicable operating conditions. The Math Behind 450 CFM A 700-cubic-foot patient compartment paired with a 450 CFM fan gives us a simple example. When used with Frazer’s dedicated, self-contained 120V AC heating, ventilating, and air conditioning system, the calculation looks like this: Air Volume ÷ Airflow = 700 ft³ ÷ 450 CFM ≈ 1.55 minutes This calculation represents how long it takes the blower to move an air volume equal to a 700-cubic-foot compartment through the system. It should not be confused with replacing every bit of cabin air with fresh outside air. In practical terms, higher circulation helps keep conditioned air moving and can reduce stagnant areas and uneven temperatures inside the module. What the Specifications Mean in the Field Technical Specification What It Means for Your Department 450 CFM circulation blower The blower can move an air volume comparable to the patient compartment through the system about every two minutes, helping keep conditioned air moving throughout the module. Independent 120V AC power The module HVAC can run from an independent power source instead of depending only on chassis-driven HVAC components. This can reduce the need for chassis high-idle solely to power module climate control. Self-contained, side-mounted HVAC The HVAC unit is located in an exterior compartment instead of on the roof. The design provides direct service access and allows modular replacement. Point-to-point 12V and 120V wiring The electrical architecture uses conventional wiring, relays, and fuses, allowing qualified technicians to troubleshoot many circuits with common diagnostic equipment. Isolated Cab Ducting and Air-Treatment Options Frazer separates patient-compartment airflow from the chassis cab HVAC configuration. This isolated ducting helps limit the movement of odors and airborne particles between the patient compartment and driver cab. Departments can also evaluate additional air-treatment equipment based on their needs. Available technologies may supplement physical filtration by treating air as it moves through the system. Because performance varies by equipment and operating conditions, departments should review the manufacturer’s documentation for any selected air-treatment system before including specific performance requirements in a vehicle specification. In-Plenum UV Air Purification: Active Neutralization vs. Passive Trapping Standard emergency vehicle climate systems rely on passive media filters that simply catch particulate matter until saturated. Frazer’s HVAC architecture pairs physical filtration with an active UV and photocatalytic purification plenum. Utilizing systems like the Dometic BreatheEasy™ platform, ultraviolet light works with nano-mesh filters and ionization directly inside the airflow stream. Instead of waiting between calls for a static cleanup, module air is dynamically treated as it circulates during patient transport. This design helps neutralize airborne biological contaminants, volatile organic compounds, and foul odors before they can settle in the compartment. Field Service and Cab Isolation This purification assembly is engineered directly into Frazer’s independent 120V AC system. Because patient compartment ducting does not connect to the driver cab, treated module air remains completely isolated from the front seats, protecting driving personnel from unwanted cross-exposures. For fleet maintenance teams, keeping the system running requires no specialized contractor teardowns. The physical filter media (Frazer Part No. 35901) and active UV bulbs are designed to be fully field-replaceable by in-house technicians using basic hand tools, protecting vehicle uptime while supporting clean air for your crews. Why HVAC Performance Can

Wood-Free EMS Modules: Why Materials Matter for Cleaning, Durability, and Long-Term Fleet Costs

Wood-Free EMS Modules: Why Materials Matter for Cleaning, Durability, and Long-Term Fleet Costs After a difficult call, crews need to clean, restock, and get their vehicle back into service. But what happens when fluids make their way past the surfaces crews can see? If porous materials are underneath, moisture and contaminants may be harder to address and can contribute to odors or material deterioration over time. That is one reason construction materials deserve a closer look when your department is specifying its next emergency vehicle. A wood-free module can help create an environment that is easier to maintain while supporting the long service life departments expect from a major fleet investment. Why Can Decontamination Affect Traditional Emergency Vehicle Modules? Emergency vehicle construction varies by manufacturer. Some designs may use plywood subflooring or other wood-based materials behind flooring, cabinet surfaces, wall panels, or other interior components. Those materials are usually hidden during everyday use. The concern begins when moisture gets past the finished surface and reaches a porous material underneath. Repeated exposure to moisture and cleaning chemicals can contribute to swelling, delamination, retained odors, or deterioration depending on the material and construction method. Where Wood May Be Used in Emergency Vehicles Depending on the manufacturer and vehicle design, wood-based materials may be used as subflooring or as backing behind cabinets, walls, seating components, and other finished surfaces. These materials can include plywood, marine plywood, particleboard, oriented strand board (OSB), or other wood-based products. Frazer takes a different approach. Our module structure uses welded 6061-T6 structural aluminum tubing rather than wood reinforcement. The base frame uses 3″ x 1.5″ x 3/16″ tube and channel, creating a rigid aluminum structure designed for the demands of emergency vehicle service. What Happens When Moisture Gets Below the Surface? Emergency vehicle cleaning may involve hospital-grade disinfectants, diluted bleach solutions, quaternary ammonium compounds, hydrogen peroxide solutions, and other approved cleaning products. These products are part of routine infection-control practices, but liquids can sometimes find their way through seams, mounting points, floor transitions, or other openings. If that liquid reaches a porous substrate, the material can absorb moisture. Depending on the material and the amount of exposure, that can contribute to swelling, adhesive deterioration, retained contaminants, or persistent odors. More scrubbing on the finished surface does not solve a problem occurring underneath it. Non-porous aluminum and stainless steel do not absorb liquids the way wood fibers can. That gives departments one less hidden material concern when they think about cleaning and long-term vehicle durability. How Can Wood-Free Construction Support Faster Turnaround? Every minute an EMS vehicle spends out of service matters. After a fluid-heavy call, crews may need to clean blood, vomit, irrigation fluids, and other contaminants from floors, cabinets, walls, seams, and equipment mounting areas before returning the unit to service. A wood-free module does not eliminate the need to follow proper cleaning procedures, chemical dwell times, or your department’s infection-control protocols. What it can do is reduce reliance on porous materials underneath the surfaces crews are cleaning. Aluminum cabinetry, structural aluminum, and stainless steel cladding are designed to resist fluid absorption and allow accessible surfaces to be cleaned without the same concerns associated with exposed wood fibers. Turning Cleaning Time Back Into Street Time For a busy 911 system, cleaning time is also fleet availability time. A unit sitting in the wash bay is a unit that is not covering its normal response area. When departments can make the cleaning process more straightforward without compromising their infection-control procedures, crews can move toward restocking and returning to service more efficiently. That benefit can add up across a fleet. Even modest improvements in turnaround time can give departments valuable operational time back during high-volume shifts while reducing unnecessary cleaning effort for crews. Looking Beyond Surfaces: Airflow and Disinfection Systems Cleaning surfaces is only one part of infection control inside an emergency vehicle. Departments may also consider how the vehicle manages air, how the patient module is separated from the cab, and whether additional disinfection technologies fit their operating procedures. Why Module Materials Matter With Misting Systems Some departments use portable or integrated misting systems as part of their infection-control process. Aerosolized products can reach areas around seat bases, access panels, floor transitions, and other spaces that may be difficult to reach by hand. If moisture reaches porous materials, it may remain there longer than it would on a non-porous metal surface. Departments considering these systems should look beyond the visible interior finishes and ask what materials are being used underneath them. Have a question for the team? Ask a Question Integrated Disinfection and Air Treatment Options Frazer offers options that can become part of a department’s broader infection-control strategy. The available Sentinel Vehicle Disinfection System provides an integrated misting solution that crews can activate from an exterior control, while the available Dometic BreatheEasy system uses ultraviolet light and photocatalytic technology as part of its air-treatment process. These systems do not replace your department’s established cleaning and infection-control procedures. They provide additional tools agencies can consider when configuring a vehicle around their specific operational needs. Independent HVAC for the Patient Module HVAC design is another important difference to consider. Frazer uses a dedicated independent 120V AC HVAC system for the patient module. Because the module climate system operates separately from the chassis climate controls, crews can manage the patient-compartment environment without depending on the chassis engine’s HVAC system. The system can operate from Frazer’s onboard power solution or shore power. This independent approach is a long-standing part of the Frazer design philosophy and gives departments greater control over the environment where their crews and patients spend their time. How Does Construction Affect Future Remounts? A remount gives an agency the opportunity to move an existing module onto a new chassis when the module remains suitable for continued service. That makes the condition of the module especially important. Damage or deterioration discovered in floors, backing materials, structural components, or other areas can add repairs, time, and expense to a

Beyond the ER: Custom Mobile Healthcare Clinics and California’s Frontline Outreach

Beyond the ER: Custom Mobile Healthcare Clinics and California’s Frontline Outreach For public health directors and EMS leaders across California, healthcare is moving beyond hospital walls. Street medicine, community paramedicine, preventive care, behavioral health, and other outreach programs are bringing clinical teams directly to the people they serve. That creates a practical question: What kind of vehicle can reliably support the team, equipment, power needs, and working environment required for regular field care? A purpose-built custom mobile healthcare clinic can provide an outpatient-style exam space wherever care is needed. The goal is simple: give healthcare teams a dependable place to work while creating a comfortable, professional environment for patients. How do you power medical equipment without draining the vehicle battery? One option is to separate clinical power needs from the vehicle’s automotive electrical system. An independent 120V AC auxiliary power source can operate configured diagnostic equipment, refrigeration, lighting, and air conditioning while the truck engine is shut off. This approach reduces the demand placed on chassis batteries and alternators during stationary operations and gives clinical teams a dedicated power source for the work happening inside the module. Why California Outreach Programs Need the Right Clinical Platform Emergency department crowding remains a challenge for healthcare systems. Non-emergent 911 calls, unmanaged chronic conditions, behavioral health needs, and limited access to routine care can all increase pressure on emergency departments and local response systems. Programs such as CalAIM, street medicine, and community paramedicine create more ways to deliver care where people live. But moving care into the field also means choosing a vehicle that can support clinical equipment, patient privacy, staff comfort, and long periods of stationary operation. Repurposed emergency transport units present a challenge. Those interiors are generally designed around acute stabilization and cot transport. Depending on the configuration, they may offer less room or privacy for preventive exams, consultations, behavioral health intake, and other outpatient services. A purpose-built clinic gives outreach programs another option. Instead of adapting a transport environment to clinical outreach, the vehicle can be configured around how the team plans to provide care. Power Independence in the Field What happens when the clinic needs power for hours at a time? Point-of-care analyzers, medication refrigerators, exam lighting, computers, and telehealth equipment can create a significant electrical demand during a deployment. The issue becomes more important when the chassis electrical system is expected to support those loads while the vehicle remains parked. Frazer addresses this by using an independent 120V AC auxiliary power system for the clinical module. Depending on the configuration, this may include a Cummins Onan gas or diesel generator or a Mobile Electric Power Solutions system. For the team in the field, that means configured workstations, lighting, refrigeration, and other supported equipment can operate while the truck engine is shut off. This can reduce unnecessary engine idling and lessen demand on the chassis alternator and batteries. Chassis warranty coverage remains subject to the applicable OEM warranty terms and conditions. Supporting Sensitive Medical Equipment Blood analyzers, centrifuges, pharmaceutical refrigeration, computers, and other sensitive equipment can be affected by power interruptions or changes in voltage. Some chassis-dependent systems use load management that can reduce electrical demand when certain operating thresholds are reached. In a mobile clinic, an unexpected interruption may affect medication storage, specimens, refrigeration, or diagnostic equipment. A dedicated 120V AC system gives configured clinical equipment its own source of power rather than depending entirely on the truck’s automotive electrical system. Backup Lighting When Primary Power Is Unavailable Frazer also incorporates a secondary 12V DC circuit tied to the chassis batteries. It is designed to provide backup power for essential interior lighting if primary generator power becomes unavailable. That gives the team light while they wrap up patient care and address the power interruption. Climate Control for California Heat California outreach teams may work in the Central Valley, Inland Empire, desert communities, and other locations where summer temperatures rise above 100°F. During those deployments, climate control affects more than comfort. It can also matter for staff working conditions and temperature-sensitive supplies. Vehicle air-conditioning systems that depend on the chassis may perform differently during long periods of stationary use, depending on the platform and conditions. Frazer uses a self-contained 120V air conditioning system that operates independently from the chassis air-conditioning system. The side-mounted system provides 15,000 BTUs of cooling capacity and is engineered to maintain a temperature differential of 35°F or more from outside ambient air. A 450 CFM blower circulates the module’s cabin air approximately every two minutes to help distribute conditioned air throughout the workspace under ideal conditions. The air-conditioning system is backed by a four-year parts-and-labor warranty, subject to applicable warranty terms. Separate Air Paths and Available Air Treatment Respiratory screenings and other community health programs may also benefit from a vehicle designed with airflow separation in mind. Frazer’s module HVAC system does not share ductwork or air handling with the driver cab, creating separate air paths between the two spaces. Available Dometic BreatheEasy integration adds photocatalytic air treatment using ultraviolet light and nano-filter technology designed to treat airborne contaminants, bacteria, and odors within the unit. A Serviceable, Modular HVAC Design When an automotive air-conditioning system is integrated throughout the engine bay and chassis, certain repairs can become more involved. Frazer’s system uses a self-contained, side-mounted assembly designed for modular replacement. When replacement is needed, fleet mechanics can remove and replace the HVAC assembly in under one hour. Frazer has documented a replacement completed in 45 minutes. The goal is straightforward serviceability and less unnecessary downtime. Designing a Clinic Around Patients and Clinical Work Not every patient wants to receive care in an environment that feels like an emergency transport vehicle. That can be especially important for preventive care, behavioral health, and harm reduction. A dedicated outpatient-style environment can give clinical teams room to work while providing patients with greater privacy and a setting designed specifically for consultation and treatment. Creating a Quieter Space for Care Behavioral health conversations, social work intake, and routine physical

Meeting California’s Complex EMS Demands: A Guide to Fleet Longevity, Infection Control, and Proactive Design

Meeting California’s Complex EMS Demands: A Guide to Fleet Longevity, Infection Control, and Proactive Design For California fire chiefs, EMS directors, and fleet managers, keeping frontline emergency vehicles ready for service can be a challenge. Long hospital offload delays, extreme summer heat, high engine idle time, and regional clean-air requirements can all put added strain on equipment. Consistent California EMS care depends on vehicles designed with those real-world conditions in mind. Frontline diesel chassis may spend hours idling outside emergency departments to support climate control, lighting, and electrical equipment. Over time, that can add engine hours, increase wear, place added demand on batteries and alternators, and contribute to exhaust aftertreatment issues. Crews may also face high call volumes, biological contamination, extreme temperatures, and limited airflow inside the patient compartment. California agencies also manage Ambulance Patient Offload Time (APOT) requirements, local anti-idling rules, and expanding community healthcare programs supported by initiatives such as CalAIM. These demands give purchasing teams another reason to think beyond initial purchase price. Structure, sanitation, climate control, power, serviceability, and remount potential all play a role in long-term fleet performance. 1. The Operational Pressures Facing California EMS Fleets California emergency fleets operate in a wide range of environments. One department may respond through crowded city streets, steep mountain roads, and coastal areas exposed to salt air. Each setting creates different demands on the chassis, module, electrical system, and climate-control equipment. Summer conditions can be especially tough. In the Central Valley, Inland Empire, and high desert, pavement temperatures can climb well above 100°F. When a unit sits outside an emergency department during a long offload delay, radiant heat from the road can raise the load on the climate-control system. Systems that depend on the chassis engine for patient-compartment cooling may require the engine to remain running during that wait. That stationary operation can add wear. High idle adds engine hours even when the vehicle is not moving, while modern clean-diesel systems still depend on the right operating conditions to manage exhaust particulates. Long periods of low-load idling may make passive regeneration more difficult and can contribute to soot buildup or exhaust-filter loading. A more integrated vehicle design can help agencies manage these concerns together. Independent auxiliary power, stable climate control, durable construction, and easy-to-clean interior materials can support uptime while giving fleet teams simpler systems to maintain. Have a question for the team? Ask a Question 2. Infection Control Starts Below the Surface In busy EMS systems, crews regularly work in difficult sanitary conditions. Disinfectants and cleaning procedures matter, but infection-control planning should also consider what is underneath the finished surfaces of the patient compartment. Modules built with plywood, particleboard, or other organic substrates may face added maintenance concerns if moisture or contaminants reach seams, penetrations, or damaged surfaces. Over time, absorbed moisture can contribute to swelling, softening, delamination, odor, and cleaning challenges. What does that mean in the field? Frazer modules use no wood, composite pressboard, or plywood in the module structure. The frame is built from welded structural aluminum tubing, exterior panels use aluminum, and interior areas use non-porous materials such as stainless steel. This construction is designed to reduce the opportunity for spilled fluids, moisture, and cleaning chemicals to soak into structural wood substrates. For crews and fleet teams, that can make routine cleaning and long-term sanitation simpler. Wood-free construction also avoids concerns tied directly to moisture-damaged plywood subfloors or wood-based cabinetry attachment points. These inorganic surfaces provide a durable foundation for routine cleaning and may be paired with additional decontamination tools, including the Sentinel Vehicle Disinfection System and ultraviolet light packages. For a closer look at inorganic materials and sanitation durability, read Wood-Free EMS Modules: Why Materials Matter for Cleaning, Durability, and Long-Term Fleet Costs. 3. Air Quality and Thermal Management During Urban Staging Air quality affects crew comfort and the patient-care environment. In heavy traffic, vehicles may be surrounded by exhaust, dust, heat, and strong odors. Inside an enclosed patient module, airflow and ventilation capacity become an important part of keeping that environment comfortable and manageable. In independent double-blind market research conducted by Smart Advantage, Inc. with 100 verified municipal and private EMS leaders, 76% identified HVAC and air filtration as a safety feature that influenced vehicle selection. That ranked ahead of crash-test results at 70% and seat positioning at 66%. Frazer addresses this need with a self-contained HVAC system built for the patient module. The module climate system operates separately from the OEM cab climate system, helping keep patient-compartment airflow separate from the driver’s cabin. Because the module HVAC system does not share ductwork with the cab, airflow remains separated between the two spaces. That design may help reduce cross-circulation of airborne particles, odors, and chemical vapors between the patient compartment and driver area. The patient compartment uses a 450 Cubic Foot per Minute (CFM) blower designed to circulate the module air approximately every two minutes. Powered by an independent 120V source, the system is designed to maintain up to a 35°F difference from outside temperature. At 105°F outside, that capacity is intended to support a patient-compartment temperature near 70°F without using the truck drivetrain as the primary source of module HVAC power. For more detail on ventilation and filtration, visit Clearing the Air: How High-Capacity HVAC Protects Crews on Challenging Calls. 4. Taking Healthcare Into the Community California fire and EMS systems often serve vulnerable populations, people experiencing homelessness, and patients dealing with behavioral health or chronic medical needs. When every concern depends on a traditional 911 response and emergency-department transport, the system can face additional pressure and longer hospital wall times. Healthcare systems and public health agencies are increasingly using mobile healthcare units to bring care directly into communities. Programs supported by California’s CalAIM initiative may use mobile platforms for preventive care, wound management, harm-reduction services, chronic disease screening, and other field-based healthcare services. Commercial van conversions can work well in some settings, but extended mobile-clinic use may call for more interior workspace, privacy, or electrical capacity. Depending on

Surviving California Wall Time: Independent Power for Urban EMS Idling

Surviving California Wall Time: Independent Power for Urban EMS Idling Urban emergency response vehicles can spend hours parked with the chassis engine running. Those extra engine hours can add wear and may contribute to diesel particulate filter (DPF) soot buildup, even when road mileage stays relatively low. For fleets dealing with frequent hospital staging, EMS urban stationary idling is worth a closer look. Frazer uses independent power to separate patient-compartment HVAC and electrical loads from the chassis engine. With the right operating setup, crews can shut down the chassis engine during longer staging periods while the independent power system continues to support module cooling and electrical needs. This approach can also reduce the need for added electrical connections to factory chassis systems and may help fleets lower long-term maintenance costs. For departments in places such as Fresno, Riverside, and Los Angeles, this can matter during long hospital offload delays and other stationary operations. Some emergency vehicles may log thousands of engine hours each year while traveling fewer than 25,000 road miles, which means the hour meter can tell a very different story than the odometer. 1. Why Urban Staging Can Be Hard on Modern Drivetrains Fleet maintenance teams need emergency vehicles ready to respond. During long hospital staging periods, shutting down a traditionally configured vehicle may also remove chassis-dependent air conditioning and electrical power from the patient module. To keep the compartment cool and equipment powered, crews may leave the chassis engine running at high idle. Engine Hours vs. Odometer Miles Odometer mileage only shows part of a vehicle’s workload. A unit may end the year with relatively low road mileage but far more engine use than the odometer suggests because of long periods spent idling (i.e. ghost miles). Whether navigating stop-and-go metropolitan hospital staging or demanding rural and mountain transit corridors, operating conditions dictate mechanical wear across both chassis drivetrains and module structures. Diesel engines can benefit from sustained operating loads that raise exhaust temperatures. Those higher temperatures help support passive oxidation of soot trapped in the DPF. During stationary idling, lower engine loads can produce cooler exhaust conditions, which may allow soot to accumulate and can lead to warning indicators or other concerns. DPF, DEF, and Derate Concerns When soot reaches programmed thresholds, the engine control module may call for an active parked regeneration. In some conditions, the vehicle may also reduce available power as part of its protection strategy. Severe faults can create a major operational problem for a frontline emergency vehicle. Low exhaust temperatures can also affect Diesel Exhaust Fluid (DEF) system performance. Under certain conditions, deposits can form in injectors or decomposition tubes and contribute to Selective Catalytic Reduction (SCR) fault codes. When that happens, maintenance teams may need to clean filters, replace sensors, or resolve diagnostic faults while a reserve unit fills the gap. 2. Comparing Idle-Mitigation Approaches Fleets looking to reduce stationary engine run time may consider several approaches, including automatic stop-start systems, auxiliary battery systems, and independent power. Each option has different installation requirements, electrical architecture, operating cycles, and maintenance considerations. What is the difference between auto-stop/start and independent power? Some auto-stop/start systems connect to chassis electrical or control systems and cycle the primary engine based on temperature, voltage, or other operating conditions. Independent power takes a different approach by placing patient-compartment HVAC, lighting, and applicable clinical loads on a dedicated 120V power source. This can allow the chassis engine to shut down when operating conditions permit without making it the primary source of module power. Architectural Feature Conventional High-Idle Aftermarket Auto-Stop Kits Frazer Independent Power Primary Power Source 6.7L propulsion diesel engine Intermittent chassis engine cycling Dedicated 120V generator platform, including Onan, MEPS, or hPower Chassis Electrical Impact Places charging demand on chassis alternators May require integration with factory chassis wiring or control systems, depending on configuration Designed to keep primary module power separate from factory chassis wiring Chassis OEM Warranty Considerations Coverage depends on OEM terms and the cause of a specific failure Aftermarket modifications may affect warranty evaluation depending on installation and the cause of a specific failure Designed to limit aftermarket electrical modifications that could become part of a warranty evaluation Starter and Battery Duty Continuous chassis charging demand while operating Repeated engine restarts can add starting-system cycles Allows the chassis starting circuit to remain inactive while independent module power is in use Severe Heat Performance Depends on chassis HVAC configuration and operating conditions Cooling may vary as the engine cycles, depending on configuration Continuous 450 CFM cooling with a 35°F+ temperature differential Backup Power Depends on vehicle configuration May include a secondary battery bank Intelligent 12V DC chassis fail-safe backup Repeated Stop-Start Cycles An auto-stop/start system may monitor interior temperature and battery voltage, then shut the chassis engine down when programmed conditions are met. When temperature rises or voltage drops, the system starts the engine again. On a hot hospital apron, cabin temperature can rise quickly. That can lead to repeated starter, ring-gear, and battery cycles over the course of a shift. Fleets considering these systems should evaluate how those cycles may affect maintenance over time and whether temperature or voltage changes could matter for the equipment carried onboard. Have a question for the team? Ask a Question OEM Warranty Considerations Warranty questions can become more complex when a chassis manufacturer, dealer, and aftermarket upfitter are all involved. If a failure involves a modified engine harness or added high-output alternator, the chassis dealer may review whether that equipment contributed to the problem before deciding how warranty coverage applies. For that reason, some fleets may prefer a design that limits changes to factory wiring and computer modules. Actual chassis warranty coverage always depends on the applicable OEM warranty terms and the facts of the specific repair. 3. How Independent Power Reduces Chassis Dependency Frazer separates primary module power and climate-control loads from the truck drivetrain. Instead of using the chassis engine as the main stationary power source for the patient compartment, the module uses a dedicated 120V