Cylinder Procedure Op No. 376

Question 1

How can gases be stored in cylinders?

Answer 1

Op No. 376 Section 1.3

Gases are stored in either a liquefied form (e.g. LPG), as a compressed gas (e.g. oxygen), or, in the case of acetylene dissolved in a solvent and stored in special cylinders containing a porous mass within the steel shell.

Question 2

Name the ways Cylinders are constructed.

Answer 2

Op No. 376 Section 1.4

• Welded cylinders: two steel halves welded together around the centre.
• Drawn steel: a single steel skin containing no weld.
• Aluminium cylinders: lighter in weight than steel cylinders and used to contain specialist gases.
• Composite cylinders: a woven “fabric” jacket impregnated with resin and protected by a hardened plastic outer cage. This type of cylinder is mainly used for LPG but can be found with various contents. Occasionally these cylinders can have an aluminium inner lining.

Question 3

When is a cylinder, regardless of their contents, are at greatest a risk of failure when subjected to direct flame impingement?

Answer 3

Op No. 376 Section 2.1

300oC for steel,
200 – 250oC for aluminium.

Question 4

How can you tell if a composite cylinder is involved in direct flame impingement?

Answer 4

Op No. 376 Section 2.2

The cylinder may become porous, this will be evident by a substantial increase in the size of the fire as it will be fed by the gas from inside the cylinder.

Question 5

Who can advise at a Cylinder incident?

Answer 5

Op No. 376 Section 1.7

Hazardous materials and environmental protection officer (HMEPO) .
British Compressed Gas Association (BCGA) competent person (BCGA CP).
The Scientific Adviser.

Question 6

When should a Hazard Zone (HZ) be implemented?

Answer 6

Op No. 376 Section 2.7

Any steel cylinder, if it is at risk of failure (i.e. it has been substantially heated, or is being subjected to direct flame impingement) an initial Hazard Zone (HZ) of 200m must be implemented around any cylinder. However, full consideration should be given to the availability of substantial cover and how this may allow the initial HZ to be reduced.

Question 7

What are the Hazard Zone of a Cylinder Incident?

Answer 7

Op No. 376 Section 2.7

Initial hazard Zone of 200m - unless substantial cover is available ( Consult HMEPO )
25m - Fire ball
200m - Debris can be projected
Cylinder itself can be propelled up to 200m

Question 8

What risks do cylinders pose?

Answer 8

Op No. 376 Section 2.9

Flammable. 
Toxic.
Corrosive.
Asphyxiant.
Cylinders which are found to be leaking should be treated as a hazardous materials incident and Policy number 796 – ‘HAZMATS; fires and incidents involving hazardous substances’ applies.

Question 9

Pre- planning - name 3 ways this can be done.

Answer 9

Op No. 376 Section 3.1

• 7 (2)(d) visits.
• Local knowledge.
• Operational risk database on the mobile data terminals (MDT).

Question 10

What considerations should be given on-route to a suspected or confirmed Cylinder incident?

Answer 10

Op No. 376 Section 3.2

• A safe route of approach and the subsequent positioning of appliances.
• The possibility of acetylene cylinders being involved.
• The use of the initial hazard zone overlay.
• The surrounding risks that may become involved if a HZ is implemented – railway lines, major roads or public buildings etc.
• Early notification to Brigade Control of an appropriate RVP.
• Any additional information received from Brigade Control or locally.

Question 11

What actions should be considered on arrival?

Answer 11

Op No. 376 Section 4.2

Appliances - park behind suitable protection from a cylinder should it fail.
Early consideration is given to RVP and approach route which.
Reduces the potential for oncoming vehicles travelling through any intended HZ.

Question 12

What should the I/C initial actions be?

Answer 12

Op No. 376 Section 4.3

As a cylinder is discovered at a fire, regardless of the contents, ICs should make every effort to extinguish any fire affecting the cylinder and apply a cooling spray directly onto any affected cylinders. This will immediately begin to restore the tensile strength of the cylinder and reduce the likelihood of cylinder failure. (In the case of composite cylinders the application of the cooling water will prevent further breakdown of the resin). This needs to be carried out from behind substantial cover such as suitably constructed double skin brick wall.

Composite cylinder that has failed should be allowed to burn off whilst protecting surrounding risks.

Question 13

What should initial crews do when discovering a cylinder?

Answer 13

Initial crews discovering a cylinder should make every effort, without exposing themselves to un-necessary risk, to identify the type, size, contents, location and number of any cylinders involved.

Crews should lash off branches set on cooling spray and then withdraw. Where crews are unable to lash off branches, the use of ground monitors should be considered by the IC.

Question 14

What message should be sent when Cylinders are confirmed?

Answer 14

Op No. 376 Section 4.5

Once cylinders have been confirmed at an incident the IC should send an informative message: “From……………. At……………. 1 industrial unit 20m x 20m, 15% alight, 1 x 85Kg acetylene cylinder confirmed involved, cylinder procedure being implemented”.

Question 15

What actions should the I/C take?

Answer 15

Op No. 376 Section

4. 7 If following a dynamic risk assessment the IC can determine that all of the following can be established:
   (i) The fire has been extinguished.
   (ii) The cylinder(s) are definitely not acetylene.
   (iii) All the cylinders present have been located.
   (iv) The cylinders involved are receiving direct cooling.
5. 8 Then the cylinder(s) can be considered as in no immediate danger of failing and it is NOT necessary to implement a 200m hazard zone. Following a risk assessment, only a cordon around the incident sufficient to maintain a safe system of work (SSOW) is required.
6. 9 After cooling, the cylinder(s) should be checked with a TIC to ensure a return to ambient temperature i.e. where the cylinder is similar in temperature to it’s surroundings (in the case of acetylene or unidentified cylinders this cooling will last for 1 hour). Crews working within 25m of the cylinder should be rigged in full structural fire fighting PPE (BA, fire kit, fire hood, gloves) at all times. The IC should then send a message stating the highest temperature recorded and tactical mode. Where a HZ still exists (acetylene or unidentified cylinders) this should be included in the message.
7. 10 Any cylinders that have not been involved in the initial fire, but are at risk of becoming involved, should be removed to a place of safety. Firefighters need to remain aware of their surrounding and ensure cylinders are moved safely. Visual indicators that a cylinder has not been involved could include

Question 16

What visual indicators are there of a Cylinder NOT involved on Fire?

Answer 16

Op No. 376 Section 4.10

• Paper labels and plastic rings are intact.
• The paintwork has not been blackened or blistered.
• The supply hose pipes are undamaged.

Question 17

What secondary actions should be taken at a Non Acetylene Fire?

Answer 17

Op No. 376 Section 4.13

Where cylinders that have been confirmed as not containing acetylene are involved in a fire, the IC should consider implementing a HZ of 200m (See appendix 3 for further details of HZ management). However, the time to do this compared to the time taken to cool the cylinder will need to be taken into account.
4.14 A HZ is not an exclusion zone; crews may work in this area following a risk assessment by the IC. When working within the HZ crews must work behind substantial cover where available and be wearing full structural fire fighting PPE (fire kit, fire hood, gloves). Where crews are working within 25m of a heated cylinder BA should also be worn.

Question 18

What should a Informative message include?

Answer 18

Op No. 376 Section 4.15

• Actions taken.
• The number of evacuees.
• The HZ size and road closures.
 The RVP and approach route.
• The tactical mode.

Question 19

What actions should be taken if confirmed Acetylene?

Answer 19

Op No. 376 Section 4.17

If the cylinder(s) has been identified as acetylene, or if he IC either suspects that the cylinder may be acetylene or cannot determine the cylinder contents, the IC should implement a HZ of 200m making use of all substantial cover to reduce the zone where possible.

Question 20

How long should a Non Acetylene Cylinder be cooled for?

Answer 20

Until confirmed cool using a T.I.C.

Question 21

What is the C.A.P test?

Answer 21

Cylinder Assessment Process.

Question 22

What does the C.A P test involve?

Answer 22

C.A.P test is used when an a cylinder is confirmed or suspected to be acetylene.

Stop the application of cooling water after 1 hour.

Monitor the cylinder with a Thermal Imaging Camera (TIC) and record temperature.

Observe for any violent steaming* or rapid drying out of the cylinder.

Leave cooling water off for 15 minutes.

Apply a momentary spray of water to the cylinder then shut off.

The CAP process is repeated 4 times (a total of 1 hr)

If, at any time, the cylinder is deemed to have failed the CAP then cooling water should be immediately re-applied for 1 hour before recommencing the CAP.

Question 23

What number Aide Memoir is the C.A.P test

Answer 23

No. 6