Trolley-mounted fire extinguishers

A hand extinguisher gives you a few kilos of agent and around fifteen seconds of discharge from two or three metres away. On a transformer yard, a fuel loading point, a bulk store or a plant floor, that is not a proportionate response to the risk — the fire will be larger than the unit before anyone reaches it, and the operator needs to stand further back than a hand unit allows.

A trolley unit answers both problems: substantially more agent, a discharge measured in tens of seconds, and a hose that lets the operator work from a standoff. It is still a first-aid appliance operated by one person, which is exactly its role in the gap between the portable inventory and the fixed system or the brigade.

What it needs from the design is access. A wheeled unit is useless if it cannot be got to the fire — the route has to be hard-standing, kerbs and steps have to be considered, and the parking position has to be upwind and clear. We survey the routes as part of specifying these, supply and site the units, and cover the annual check, refilling and pressure-test cycle under contract.