construction begins. Any changes you make
after you sign on the dotted line become costly
If you’re interested in a safer and more
ergonomically designed ambulance, carefully
review the Ambulance Patient Compartment
Human Factor Design Guidebook, published by
the Department of Homeland Security. 4 New
research indicates that we need to change the
patient compartment layout to improve safety.
The guidebook will help you develop a safer
and more efficient patient compartment that’s
right for your service and the type of work you
need to do in it.
CHASSIS & SUSPENSION SELECTION
The chassis and suspension are extremely
important to the overall safety of your vehicle.
An undersized, overloaded ambulance chassis
moving down the road with lights and siren
is an accident waiting to happen.
Gross vehicle weight rating (GVWR) is
the maximum operating weight (i.e., mass)
of a vehicle specified by the manufacturer.
GVWR includes the vehicle’s chassis, body,
engine, engine fluids, fuel, accessories, driver,
passengers and cargo. Driving any vehicle over
its GVWR leads to increased brake wear and
makes stopping the vehicle problematic and
dangerous, especially at higher speeds.
The type of work your agency does will
dictate your chassis options. Available payload
changes with each size chassis. For example,
a light chassis (GVWR 8,000– 10,000 lbs.)
may work well for an ambulance service that
carries no firefighting gear and may not need
A light chassis will be easily overloaded if
you add the firefighting equipment used by
many departments: bunker gear, SCBAs, forcible entry tools, thermal imagers, extrication
equipment, water/ice rescue suits, wildland
gear, mass casualty incident bags, fire extinguishers, hand tools, etc.
Inventory all equipment and supplies you
typically carry and carefully estimate the total
weight. Always weigh your ambulance as it
leaves the factory and again when it’s fully
loaded with the crew inside.
To add a margin of safety, select a chassis
that exceeds your estimated payload. If you
don’t do this, you may find that your chassis
exceeds the recommended GVWR.
Most consumers don’t understand that all
ambulances aren’t created equal. Unless you
visit ambulance factories to see how each company builds their bodies, you’d assume that a
wall is just a wall. But there are actually structural variations hidden behind the finished
walls, ceiling and floor. When purchasing an
ambulance, you should learn what the structural components are made of and how they’re
assembled and held together.
Some manufacturers build their ambulance
box with rounded corners using extrusions
to connect the walls to each other and to the
roof. An extrusion is a hollow piece of rounded
molding that acts like a frame. Other builders use formed parts that create an integrated
module using no extrusions. Solid body construction has square edges at the corners and
the roof line.
Wall and roof construction also varies
between builders. Some manufacturers utilize spot welds, glues and double-sided tape
to build walls while other builders incorporate
fully welded seams.
The interior cabinetry can vary from wood
to metal to aluminum, and even plastic inserts.
Even insulation can differ. One builder may
spray in an expanding foam insulation while
another might use common household-type
insulation that’s glued to the walls.
The real integrity and strength of the ambulance body lies behind the finished walls. It’s
obvious when you see some ambulance boxes
being constructed that they’re built stronger
than others. Educate yourself, ask the builder
about their construction techniques, visit factories and network with other users before you
make a purchase. Most ambulance manufacturers will gladly provide you with satisfied
customers you can speak with.
People spend a lot of time sitting in ambulances, so choose seating wisely. They have to
be functional, comfortable and safe. They also
have to clean up easily after bad calls.
The industry has seen significant safety
There have been vast improvements in seating
safety and range of movement.
Photo A. J. Heightman
Some ambulance manufacturers use spot welds, glues and double-sided tape to build walls; other builders incorporate welded seams. Photo courtesy Wayne Zygowicz