Intent 1:
To exempt maintenance operations on pressurized
systems from the application of Sentence 4.5.10.7.(1) if certain
practices are carried out.
This is to limit the
probability that:
- the piping systems will leak during maintenance operations,
which could lead to the escape of liquid, which could lead to the
ignition of vapour from a nearby ignition source, which could lead
to harm to persons, and
- the maintenance operations will lead to the ignition
of vapour from the piping system, which could lead to a fire or explosion,
which could lead to harm to persons.