6. Temporal models

6.1 Principle

When a flammable gas is dispersed, the flammable volume will increase:

• until discharge is interrupted (e.g. by means of automatic valve-type isolation systems);

• or until stabilization is reached.

During this growth phase, the cloud will come into contact with various ignition sources. Depending on their location in relation to the leakage point, these sources will come into contact with the cloud at different times. Similarly, their contact time with the cloud will differ (the sources reached first remain in contact with the cloud for longer).

Following detection of the cloud, a strategy to deactivate certain ignition sources may...