Engine type & size
All heavy machinery is equipped with turbocharged engines. Turbocharged engines take in air at higher atmospheric pressures, meaning they can burn more fuel and produce more power than regular engines.
These engines also run very hot and can easily catch fire given the use. Machines that run all day, or machines that run in a landfill full of flammable trash, are at exceptionally high risk of engine fires.
To extinguish fires originating from the engine, most fire protection professionals will recommend a wet vehicle suppression system. These systems provide rapid cooling capabilities dry agent can’t offer. This type of system can also reach areas dry chemical cannot. The wet chemical agent of these systems is typically stored in tanks connected to expellant nitrogen cartridges.
Both dry and wet agent is stored in tanks. Dry chemical is stored by the pound (30-pound tank, 50-pound tank, etc.), whereas wet chemical is stored by the gallon (typically by 5, 10, or 15-gallon tanks). The amount of chemical will also determine the number of nozzles. The more nozzles there are, the more extensive the coverage area. The larger the system, the longer the nozzle discharge time as well.