Fire Safety Issue with Professional Turf Mowers

Richard L. Parish, PhD, PE

A municipal parks worker in south Louisiana was seriously injured when the professional zero-turning-radius mower he was using caught fire. Like many zero-turn mowers, the mower involved in that incident had plastic gasoline tanks mounted like fenders, over and in front of the drive tires, and thus right beside the operator. The operator was mowing around a steel frame from a picnic table. He got too close to the table frame and the right gasoline tank hit the angle iron frame, puncturing the gasoline tank. The gasoline from that tank poured out, vaporized, and ignited. The fire then caused the left tank to explode. The operator was trapped in the seat by the steering levers while engulfed in burning gasoline. In his pain and confusion, he was unable to get the levers into the neutral position so that he could fold them out of the way, and he therefore had to bend the levers out of the way before he could escape. He was severely burned by the time he got away from the burning mower.

There are two lessons to be learned from this accident:

There are some models of zero-turn mowers on the market that incorporate better designs. Some manufacturers of zero-turn mowers mount the fuel tanks in more protected locations such as under the seat and under a heavy steel plate (to further protect the operator), behind the drive wheels, or inside steel fenders or guards. Some manufacturers use steel fuel tanks. Safety considerations should be a concern when specifying/purchasing a mower. Turf professionals should specify and purchase zero-turn mowers with fuel tanks in less vulnerable locations. A zero-turn mower with exposed gasoline tanks over the wheels beside the operator is an accident waiting to happen. I recommend that all bid specs for zero-turn mowers address this issue.
Operators of zero-turn mowers need to be aware of the danger of gasoline fires on their machines and be very careful to avoid impacting the fuel tank(s) when trimming around obstacles. Any fire on a zero-turn mower will likely involve and injure the operator since the machines have open operator’s stations and are small and compact, thus the fuel tank(s) can’t be very far away from the operator. Zero-turn mowers are designed and purchased specifically for trimming around obstacles, and these obstacles certainly can puncture fuel tanks if there is a collision.