Pressurised containers are used widely and in many applications. For example, in the fire and safety industry an inert gas may be held in a container at a raised pressure. The gas may be used to suppress a fire in an environment, such as a room or aircraft, or to inflate a safety device, such as an airbag. Typically, a valve is provided that controls the release of gas from the pressurised container to the environment.
It has been found that in certain situations it may be necessary or desirable to depressurise such containers. What is desired, therefore, is an effective method of depressurising a container.