PN 806 Fireworks and Explosives

Question 1

What are Explosives?

Answer 1

Explosives are defined by the Health and Safety Executive (HSE) as 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

Explosive hazards will be identified by the term?

Answer 2

“Yankee Hazard”.

Question 3

What are the two types of explosive materials?

Answer 3

Detonating and Deflagrating .

Question 4

What is a detonating explosion?

Answer 4

Detonating explosion is described as when the reaction exceeds the speed of sound.

Question 5

What is a deflagrating explosion?

Answer 5

Deflagrating explosion below the speed of sound. However, it is not necessarily the material
that determines the rate of reaction but other factors such as pressure, heat and confinement
which all influence the rate of reaction and the hazard.

Question 6

All explosives, regardless of their contents are to be considered at the greatest a risk of
detonation whilst being subjected to what?

Answer 6

Heating.

Question 7

Many explosives are sensitive to?

Answer 7

Shock, friction, chemical reaction and some are water and grease reactive, all of which could lead to a detonation.

Question 8

It is unlikely that any explosive can be what when ignited?

Answer 8

Extinguished.

Question 9

Are metal boxes a good packaging for explosives.

Answer 9

The packaging in which the explosives are contained will directly influence the speed of the
reaction. Metal boxes will lead to mass explosion of their contents.

Question 10

In a detonation if the explosives are stored in a container this may fragment, resulting in what?

Answer 10

These fragments can be propelled at velocities three times the speed of sound and travel great distances.

Question 11

The explosion will generate a blast wave that will travel at velocities greater than the speed of
sound. This blast wave will carry a second wave of fragments called secondary fragments. The
pressure of the wave can be great enough to kill without the victim being struck by any
fragments. This is called?

Answer 11

This is called ‘over pressure’.

Question 12

Cover can be used to give a degree of protection from fragments but over pressures will what?

Answer 12

Over pressures will wrap around cover as high pressure will always move to a low pressure region.

Question 13

NATO guidance is to prohibit radio

signal within what distance?

Answer 13

600m.

Question 14

What cordons should be set for explosives up to 250kg

Answer 14

200 Metres.

Question 15

What cordons should be set for explosives up to 51kg – 2000kg and military explosive munitions?

Answer 15

600 Metres

Question 16

What cordons should be set for explosives over 2000kg?

Answer 16

1000 metres

Question 17

What restrictions should be put on the use of radios?

Answer 17

60m until it has been
confirmed that the explosives are not susceptible to
detonation from radio transmissions.

Question 18

ISO containers must be checked they are at ambient

temperature how?

Answer 18

The use of a TIC and flooded with water via a suitable

opening before doors are opened.

Question 19

What is the maximum storage of fireworks for domestic use for a shop? (KG)

Answer 19

250kg

Question 20

Gun enthusiasts must hold an?

Answer 20

“Acquire and keep certificate”

Question 21

Gun enthusiasts can hold how much black powder stored in metal boxes?

Answer 21

20kg.