Flammable and Compressed Gases

Question 1

What are the 3 States of Matter

Answer 1

1. Solid - has a fixed volume and shape2. Liquid - has a fixed volume and variable shape3. Gas - no fixed volume and variable shape

Question 2

Class of gas labels and cylinder colours

Answer 2

1. Poison Gas - White with black lettering2. Poisonous and Flammable - White and Red with black lettering3. Oxidising Agent - Yellow with black lettering4. Non Flammable - Green with black lettering5. Flammable - Red with black lettering

Question 3

Procedure to clamp off ruptured natural gas line

Answer 3

1. appliance pump engaged, crew member standing by with charged line2. Full level D with BA donned3. hearing protection e.g. ear plugs4. gas clamps - sufficient size5. tools to dig around around6. when clamping a service pipeline - one clamp on supply side should suffice7. when clamping a main distribution pipeline - a clamp either side of the damage

Question 4

What does CNG stand for

Answer 4

Compressed Natural Gas

Question 5

What is a BLEVE

Answer 5

Boiling Liquid Expanding Vapour Explosion.Term used to describe a cylinder involved in fire where the contents expand to such an extent the cylinder can no longer contain the pressure and ruptures due to structural fatigue caused by intense heat. This rupture releases large amounts of liquid gas that expands into a huge vapour cloud and burns as a fireball

Question 6

Signs of a BLEVE

Answer 6

flame impingement- discolouration of a gas cylinder- distortion of a gas cylinder- activation of the relief valve- relief valve sound becoming increasingly louder