Flashcards in Demolition Safety and Transportation (Chapter 3) Deck (43)
10. For calculating MSD, When do you refer table 6-2?
When charge weight is more than 27 lbs and less than 500 lbs
19. In temporary storage, how explosive should be stacked?
Weigh no more than 500 lbs per pile
Placed no less than 140 feet apart
3. What is minimum distance from energized power lines required to prepare electric blasting cap?
At least 155m
17. To ensure circulation of air, what is minimum distance from top of stack to ceiling or cover?
No less than 18 inches
16. To ensure circulation of air, what is minimum distance from bottom of stack to earth flooring?
No less than 3 inches
15. Where are blasting caps stored during transportation?
Transfer in separate location from the explosives
How do you calculate MSD when charge weight is more than 500 lbs?
Meters = 100 x cube root of N.E.W
Feet =300 x cube root of N.E.W
(Bare Charges in the Open)
7. Described the requirements for time fuse test burn, and how many times should be conducted?
At minimum 3 ft test burn. Do not use the first or last 6” of time fuse from a new or partially used roll (moisture) Book answer is every 24 hrs. However it should be conducted every hour.
5. Premature detonation of electric blasting caps may be induced by:
1. What are the some considerations in demolition safety?
a) Maintain Control of all initiation source at all times (i.e. RAMS transmitter, electrical blasting machines, etc.)
b) Suspend blasting operations during electrical storms
13. What is the first step you take when conducting a continuity check?
18. What is SADD?
Rules for storing explosives:
Safety is most important
6. How many people requires to conduct explosive transportation?
Use only minimum number of personnel necessary to accomplish the mission
12. How many fire extinguishers you must have when you transporting explosive and what are they?
2, Class B/C
9. What is the MSD for charges that less than 27 lbs?
22. Can you destroy blasting cap with burning method?
NO. Blasting cap destroy by only detonation
8. What is formula for DET Cord N.E.W?
Length in feet x 54 grains per foot x RE Factor = total grains of explosives
Grains / 7000 = NET EXPLOSIVE WEIGHT IN LBS
4. When placing electrical blasting caps in a metal container (like an ammo can), how much overlap should be on the lid ?
Minimum ½ inches overlap
14. How long should you wait to clear a nonelectric misfire and electric misfire?
Non-electric: 30 minutes
20. What is the preferred method of disposing of explosive?
2. Can you use BLASTING CAPS underground?
No, Do not use blasting caps underground, use DET Cord or M151/M152 boosters
21. When burning explosive what must you do?
Calculate Minimum Safety Distance
Ensure stacked pules will not exceed 2000 lbs or more than 3 inches thick
Where should you not carry blasting caps?
Pockets or in any uncontrolled container
What should you do before un-shunting wires on an electric blasting cap?
What should you do after a time fuse test burn?
Upon completion of test, mark roll with Your name, DTG, test burn time, then tie half knot in non-working end
RE factor for Det Cord
What should you avoid when working with Det cord?
Sharp bends, loops, kinks as well as stepping on the cord (Any of these can change the path of detonation and/or cause a cut in the cord)
What type of charge are the MSD's for in this chapter?
Bare Charge in the Open
Non-electric Misfire Causes
Moisture in M7 Cap, M700 Time Fuse, Det Cord
Failure to seat M700 into M7 or M60/M81
Failure to properly seat the blasting cap into the cap well or explosive
Debris in the M7