A boiler is a tank that holds a liquid (usually water) which is boiled by a heat source, the purpose of which is to produce steam under pressure in order to drive something. A pressure plant is a tank designed to hold fluids or gases at high pressure without bursting. This can include all types of object that are under pressure, such as compressed air systems, heat exchangers and refrigeration units. Both boilers and pressure plants are subject to the risk of explosion and collapse, the definitions of which follow.
Explosion means that a boiler or pressure plant is torn apart suddenly and violently by the force of internal steam (in the case of a boiler) or gas or fluid pressure (in the case of a pressure plant) and the contents escape.
Collapse means that there is a sudden and dangerous distortion of the boiler or pressure plant, with or without the container being ruptured (torn). This is due to the force of steam or, in the case of a pressure plant, fluid pressure.
Both boilers and pressure plants must be insured against damage by explosion and collapse, unless (in the case of pressure plants) these perils are caused by chemical reaction or the ignition of the contents. (This eventuality can be covered by property insurance.) However, explosion or collapse may well not only damage these objects themselves, but also have more widespread effects. Employees could be injured, an eventuality covered by employer’s liability insurance in the UK and by Berufsgenossenschaften in Germany. Public liability insurance covers bodily injury and property damage to third parties.
Damage to the policyholder’s own surrounding property which is caused by a boiler explosion is often excluded from the property policy and must be covered under an engineering policy.
In addition to covering explosion and collapse the insurance of boilers and pressure plants also includes „sudden and unforeseen damage“, which may take the form of joint leakage, the cracking of sections, weld failures and the overheating of pipes and boilers.
The main exclusions are fire, overload experiments, wear and tear, any loss for which a supplier or manufacturer is responsible, business interruption and equipment breakdown.
The duty of care is strict, and those using boilers and pressure plants are required to operate within legally defined safety limits and to ensure that their pressure systems are inspected and approved within the time limits defined by the…