Fireworks & explosives

Question 1

Definition of explosives…

Answer 1

Any material that is capable of undergoing a self-contained and self-sustained exothermic chemical reaction at a rate that is sufficient to produce substantial pressures on their surroundings, thus causing physical damage.

Question 2

What term does the LFB use for explosive hazards?

Answer 2

Yankee hazard

Question 3

Two types of explosions…

Answer 3

• Detonating, exceeds speed of sound

- Deflagrating, below speed of sound

Question 4

Explosives may be sensitive to…

Answer 4

• Heat
• Shock
• Friction
• Chemical reaction
• Water or grease reaction

Question 5

Considerations with explosives stored in containers

Answer 5

• Metal boxes will lead to mass explosion of contents

- Container may fragment causing shrapnel

Question 6

Why have you got to be cautious about using cover?

Answer 6

Cover can be used to give a degree of protection from fragments but over pressures will wrap around cover as high pressure will always move to a low pressure region.

Question 7

Who are the licensing authority for the bulk storage of fireworks?

Answer 7

HSE

Question 8

Who should SMs inform when explosive storage is identified?

Answer 8

Operational Resilience and Planning Team (ORPT)

Question 9

How do you identify a yankee hazard on the MDT?

Answer 9

Red triangle with black exclamation mark

Question 10

When explosives confirmed involved in an incident what should be sent to control and how?

Answer 10

Priority message “explosives confirmed involved”

Question 11

Operational considerations for explosives

Answer 11

• If explosives believed involved withdraw all personnel and public and set up cordon
• Do not attempt to investigate compartment/container where explosives suspected
• Explosive material once ignited will self-propergate, explode and be impossible to extinguish
• Crews must not handle explosives unless operationally imperative to move them before being involved
• Explosives must be protected from heat of adjacent fires
• Some explosives react violently with water, some are made safe. Seek advice from specialist before applying water directly

Question 12

Some of the most commonly encountered legal explosive storage

Answer 12

• Up to 250kg fireworks in ISO container for retail
• Up to 20kg black powder in metal boxes for licensed gun owners
• Bulk storage of railway fog signals in metal boxes

Question 13

Hazard zones for explosives

Answer 13

• 200m, 250kg/small car size
• 600m, 251-2000kg and any military explosives 1.2
• 1000m, over 2000kg
• HMEPO can advise

Question 14

Considerations when evacuating

Answer 14

• Use substantial cover
• Risk of flying/falling glass
• Any personnel who suffer cuts, burns and wounds while ff’ing to be withdrawn and have immediate first aid treatment

Question 15

Minimum distance from explosives to use radios

Answer 15

• 60m
• 600m for military/malicious explosives
• Specialist advice may change this

Question 16

Before opening ISO container storing fireworks involved in fire…

Answer 16

• Thorough check of container with TIC to ensure all at ambient temperature and no hot spots
• When opening doors treat as compartment fire (BA, 45mm, crew positioning etc)
• Apply water to contents using available hatches/openings
• Consider methods of making opening if none available (FRU, USAR)

Question 17

Considerations towards end of incident

Answer 17

• Residual material may be buried and ignited when turning over
• Unexploded parts may have been projected some distance
• Defensive ff’ing should be maintained until IC confident no longer any risk

Question 18

Who can the IC use for specialist advice for explosive incidents?

Answer 18

• HMEPO
• Police explosives officer
• On site specialist
• Scientific advisor