Question

A process vessel has to be shut down in order to do some internal maintenance involving welding. Assuming that it had contained flammable material and that it had been scavenged by a flow of nitrogen followed by air, what measurements would have to be made in order to ensure that the work could proceed safely? Mention any special precautions that would have to be taken.

Answer 1

Measurements to be taken:

First Check flammability limit of matarial in that vessel. it should be lesser than lower flammability limit

Check the ignition point in that vessel

check the flashpoint in that equipnet

check fire point in that vessel

Check the detector( heat detector, flame detector, smoke detector, gas detector) attached to that vessel showing signal as zero

check fire alarm is working and showing no alarm at that time

Check the extingushing elements working properly (sprinkler, extenguishing agents)

special precautions

Are work area clean

Are the right tool is provided to the personnel

Are all components Pipe and valve closed linked to that vessel