Food carts and trucks have been around for decades. Most cities have vendors using portable hot dog or ice cream carts at locations where crowds congregate. Likewise, most have the unflatteringly nicknamed “roach coaches” that show up at factories and other operations with a lot of employees.
Now, they’ve become as trendy as high-end restaurants, offering up a variety of cuisines. Some cities like Portland, Ore., have open spaces that serve as de facto food cart malls.
These Mobile Food Preparation Vehicles (MFPV) can be either a truck or a trailer pulled by a pickup truck to a predetermined or even specifically licensed location. The similarity is that both are stand-alone sites where food is prepared specifically to a customer’s order.
MFPVs can be found on street corners, at sporting events or festivals just to name a few. They are designed for people who want quick, hot food and drinks on the go without needing to sit down or spend the time waiting in long lines.
MFPVs also provide the fire service with a unique challenge. Although they must be periodically inspected by the local health department, being mobile, they do not fall under the building or fire code in most states as would, for example, a food vendor operating in a tent at a fairground where the tent is defined in the fire code as a temporary structure.
The fire service has begun to realize the severity and potential danger for serious injuries from fires within these food trucks and trailers. Let’s look at some of the hazards.
Suppression systems and LPG
First, there is cooking. We know that cooking is now the leading cause in the United States of accidental fires in the home. That risk in commercial establishments has been significantly mitigated by hood suppression systems over ovens, burners, grills and fryers.
Unfortunately, with food trucks, some or all of these cooking appliances may be present. Newer, custom-built units usually have hood suppression systems.
But those built-on converted older trucks or homemade conversions may be without the hood or suppression system. Most MFPVs carry portable fire extinguishers, but few of those are a Class K extinguisher designed to suppress grease, fat or cooking oil fires.
Second and more important for your safety, the majority of MFPVs use liquid propane gas as the primary fuel for cooking and possibly for refrigeration.
While commercial propane is colorless and odorless, it does have a mercaptan-like smell added into the mixture. If you’ve been in the fire service for five years or more, chances are that you’ve responded to a propane emergency — a leak or fire from a residential gas barbecue grill; a spill from an overfill at a residential or commercial propane tank; or a train or truck tanker venting itself on a hot summer day.
While each is dangerous, most of these hazards are relatively safe because the tank is venting outdoors and less likely to hit its flammability range or find a random ignition source.
Explosive power
MFPVs are obviously more enclosed. This allows any escaping propane, which is heavier than air, to pool near the floor until it finds one of the multiple ignition sources already present in the truck or trailer.
By comparison with the flame affect or explosive power from a 20-pound residential propane tank, most MFPVs have one or more 100-pound tanks encased or chained inside or outside the vehicle.
Where a 20-pound tank can generate over 425,000 BTUs during an explosion, a 100-pound tank can release a massive 2.5 million BTUs at once, burning and igniting everything in its path.
One of the most hazardous times for a fire or explosion is during or immediately after a manual switchover from one propane tank to another.
There are also other more common fire hazards in a food truck. One is the generator, especially in converted MFPVs, that operates the internal and external electrical needs such as refrigerators, lighting or fans.
Fires have occurred while refueling this generator. An additional hazard could come from carbon monoxide if the generator is not properly vented or from the electrical system itself.
Newer custom-built MFPVs usually have the generator in a side compartment that runs off the truck’s fuel tank, whether diesel or gasoline. Finally, as with any vehicle, there can be fire hazards associated with the engine compartment, mechanical or vehicle electrical systems.
Tactical considerations
What tactics should you employ when confronted by a fire in MFPV?
First, try to learn where or at what events food trucks may operate in your jurisdiction. Look at the food trucks, even if only through the customer window, to determine if it’s custom-built or a conversion.
Check to see if it has a hood with a built-in suppression system or uses only fire extinguishers. Look at the exits available for the employees in an emergency. Is there a rear service door available in addition to the exit through the truck cab?
Pre-incident plan those areas where the MFPVs will be situated and become familiar with the location of fire hydrants or water sources. Are those areas close to populated areas, commercial or residential buildings, critical infrastructure such as an electrical sub-station, hospital, school, stadium or university that could become a serious exposure?
Play the “what if” game. If this MFPV caught fire, how would I approach the scene, what hydrant would I take, would I automatically dispatch any additional fire units? As the officer or firefighter in charge, how would I do my 360-degree size-up?
Here are some suggestions:
- Approach the area up wind, if possible.
- Wear full PPE and SCBA.
- Confirm that LPG is the fuel and determine if there is an external gas shut-off valve.
- Stay a relatively safe distance and use a thermal imaging camera when conducting your size-up.
- Establish an appropriate incident command structure.
- Consider evacuating the area for at least 500 feet of unauthorized personnel.
- Establish tactical priorities — fire control, victim care, evacuation, a rapid intervention team, hazmat and run-off control, etc.
- Have sufficient fire personnel and apparatus on scene or nearby if things were to go awry.
- Don’t hesitate to request a structure fire response; you can always disregard any units not needed.
- Secure a large, continuous water supply, one or more fire hydrants or multiple water tenders.
- Use a large volume of water — multiple 1 ¾-inch fire lines to suppress the fire and to cool and redirect the fire away from the LPG tanks.
- If needed, use three streams of water to cover the advancing hose teams and firefighter attempting to shut down an exterior gas valve.
While each MFPV is unique and therefore can have one or more unique hazards, looking at those food trucks that operate regularly in your area, pre-planning and playing the “what if” game should help you from being surprised when and if it were to catch fire.
This article, originally posted in 2017, has been updated.
