4. Explosives for the Mining Industry

Question 1

What are the three kinds of explosions?

Answer 1

1. Mechanical
2. Chemical
3. Nuclear

Question 2

Explosive

Answer 2

a substance which when properly initiated is rapidly converted into gases at high temperatures and pressures

Question 3

Low Explosives

Answer 3

Initiated by flame (black powder)

Question 4

High Explosives

Answer 4

Cannot be initiated by flame under normal circumstances and requires shock or impact for detonation

Question 5

Blasting Agents

Answer 5

chemical mixtures containing no ingredient that is itself an explosive and requires a primer

Question 6

What are the 3 major suppliers of blasting agents?

Answer 6

1. Austin Powder
2. Dyno Nobel
3. Orica

Question 7

What 3 things are explosives made up of?

Answer 7

Fuels (chemical) + Oxidizers (oxygen source) + sensitizers (drives the reaction)

Question 8

What are 6 ideal characteristics of explosives?

Answer 8

1. Low cost
2. High energy yield per unit weight
3. Easy to handle
4. Unlimited resistance to water and low temperatures
5. Reliable initiation by detonators/primers
6. Unlimited shelf life
7. Does not create a poisonous gas

Question 9

What are 2 advantages of dynamite?

Answer 9

1. shoots under unfavourable conditions
2. very good initiation
3. excellent for urban control blasting

Question 10

What are 2 disadvantages of dynamite?

Answer 10

1. mechanical sensitivity
2. headaches
3. expensive

Question 11

What are 2 advantages of ANFO?

Answer 11

1. easy to load
2. easy and safe to manufacture
3. mechanical insensitivity
4. inexpensive

Question 12

What are 2 disadvantages of ANFO?

Answer 12

1. must be initiated with a primer

2. dissolves in water

Question 13

What are 2 advantages of slurries/watergels?

Answer 13

1. good water resistance

2. good for reliable detonation in small diameter blast holes

Question 14

What are 2 disadvantages of slurries/watergels?

Answer 14

1. may deteriorate in storage due to gel breakdown

2. becomes hard at low temperatures

Question 15

What are 2 advantages of emulsions?

Answer 15

1. very water resistant

2. very high VOD

Question 16

What are 2 disadvantages of emulsions?

Answer 16

1. expensive

2. sensitivity decreases with shelf life

Question 17

Safety Fuse

Answer 17

long thin cord of black powder wrapped in textile and covered waterproof coatings; used to set off plain detonators

Question 18

Detonators/Blasting Caps

Answer 18

most common initiation device activated by heat, shock or electric spark

Question 19

What are the 3 types of detonators?

Answer 19

1. Plain
2. Electric detonators
3. Electric delay detonators

Question 20

When do you use plain detonators?

Answer 20

when electric initiation is prohibited due to extraneous electricity

Question 21

Detonating Cord

Answer 21

connects blast hole charges so they can detonate at the same time; eliminates the need for multiple detonators

Question 22

Primer

Answer 22

cap-sensitive explosive used to initiate other explosives or blasting agents containing a detonator

Question 23

Booster

Answer 23

cap-sensitive explosive used to initiate other explosives or blasting agents not containing a detonator