VTCA Safety Seminars Blasting Safety

Size: px

Start display at page:

Download "VTCA Safety Seminars Blasting Safety"

Kristin Burns
5 years ago
Views:

1 VTCA Safety Seminars Blasting Safety

2 Blasting/Explosives Safety Definitions Blast Site Safety Pre Blast Concerns Blast Area Post Blast Exams Misfires Flyrock

3 State/Local Blasting Requirements Note: State and local blasting requirements may be more strict than the federal requirements. Some states require a new miner to attend their training program prior to entry into a mine. Virginia requires GMM Training

Blasting/Explosives Safety Definitions Surface Metal/Nonmetal Blast Site, Part 56 The area where explosive materials are handled during loading.

4 Blasting/Explosives Safety Definitions Surface Metal/Nonmetal Blast Site, Part 56 The area where explosive materials are handled during loading. This includes the 50 perimeter around the loaded holes in all directions. 50 requirement can be reduced to 30 if perimeter is demarcated with a barrier.

5 Blasting/Explosives Safety Definitions Underground Metal/Nonmetal Blast Site, Part 57 The area where explosive materials are handled during loading. This includes the 50 perimeter around the loaded holes in all directions. 50 requirement can be reduced to 30 if perimeter is demarcated with a barrier. 15 or more of solid pillar or broken rock can be substituted for the 50 distance.

6 Blasting/Explosives Safety Definitions Surface & Underground M/NM Blast Area, Part 56 & 57 The area where concussion, flying material, or gases from an explosion may cause injury to person.

7 VTCA Safety Seminars Blast Site Safety 30 CFR 56/ (a) Loading, Blasting and Security When explosive materials or initiating products are brought to the blast site, the blast site shall be attended; barricaded or posted with warning signs, such as DANGER, or Keep Out; or flagged against unauthorized entry

8 VTCA Safety Seminars Control of Blasting Operations 56/ (a) only persons trained and experienced in the handling and use of explosive material shall direct blasting operations and related activities trainees and inexperienced persons shall work only in the presence of persons trained and experienced in the handling and use of explosive materials

9 Blast Site Safety-Pre Blast Hazard Assessment Inspect the work area/blast site to be sure this area is safe to work at. Inspect the face for proper burden. Inspect the highwall edge for overhangs and undercuts.

10 Blast Site Safety - Safety Meeting Conduct pre-blast safety meeting with the blast crew. Document the meeting Review: Blast plan Any hazards in the area Loading procedures Aid in the movement of equipment Use of Wheel Chocks Use of Personal Protective Equipment Blast signals Guarding

11 Blast Site Safety-Fall Hazard Zone Visual Warnings Signs or Tape Cones or Boulders Paint or Chalk Physical Barriers Berms or Boulders Handrails Fencing Cables Belt or Harness and Lanyard Buddy System

12 Blast Site Safety - Boreholes Measure burden, spacing, and hole depth for proper measurements prior to loading.

13 Blasting Safety - Drill Logs Safety: Communication with driller and blaster to reduce flyrock. Custom load holes according to changing rock conditions. Caves/Voids. Mud seams Amount of overburden

14 Blasting Safety-Drill Logs Performance: Fragmentation with low vibration and air blast. # holes and depth. Blast hole deviation. Actual burden and spacing. Any changes to layout.

15 Blast Site Safety VTCA Safety Seminars 30 CFR 56/ (c) Loading, Blasting and Security Once loading begins, the ONLY activities permitted within the blast site shall be those activities directly related to the blasting operation

Blast Site Safety VTCA Safety Seminars 30 CFR 56/57.

16 Blast Site Safety VTCA Safety Seminars 30 CFR 56/ (c) Loading, Blasting and Security and the activities of surveying, stemming, sampling of geology, and reopening of holes, PROVIDED that reasonable care is exercised.

17 VTCA Safety Seminars Blast Site Safety/ Security feet Charged or Loaded Holes Holes 2 Loaded 7 Unloaded f e e t f e e t Uncharged or Unloaded Hole 50 feet

18 VTCA Safety Seminars Blast Site Safety/ Security Blast Site Safety (Shot Loaded) Loaded Shot 50 ft Perimeter New Drilling Permitted No Drilling Permitted Inside 50 ft Perimeter

19 Blast Site Safety - Loading When Boosters and Detonators are laid out they should be separated on the ground.

20 Blast Site Safety - Loading Primers shall only be made up at the time each hole is loaded. Do not assemble primers ahead of time and leave on the surface.

21 VTCA Safety Seminars Blast Site Safety/ Security Pre Blast Concern Premature Detonation: Activities Loading Hookup Initiation by Mechanical Electrical Chemical Thermal

22 VTCA Safety Seminars Blast Site Safety/ Security Pre Blast Concern Mechanical Premature Detonation Tamping on a primer Dropping of a large diameter cartridge on a primer Running over a primer lying on the bench Drilling into a hole containing an explosive material WHAT ELSE???

VTCA Safety Seminars Blast Site Safety/ Security 30 CFR 56/57.

23 VTCA Safety Seminars Blast Site Safety/ Security 30 CFR 56/ (b) Loading, Blasting and Security Vehicles and equipment shall not be driven over explosive material or initiating systems in a manner which could contact the material or system, or create other hazards

24 Blast Site Safety-Vehicles When out of the cab of the vehicle, the wheels of each vehicle shall be chocked. This includes all rubber tire mobile equipment.

25 Blast Site Safety - Loading Rigid cartridges of explosives 4 in diameter or larger shall not be dropped directly on the primer. Protect the primer from tamping.

26 Blast Site Safety VTCA Safety Seminars Pre Blast Concern Electrical Premature Detonation RF Energy Power Lines Lightning

27 Blast Site Safety-Loading Electrical Storms, Use the 30 Second Rule If the time between seeing lightning and hearing thunder is less than thirty seconds, you are in danger. You can turn on a AM radio to detect if any lightning is in the area. Listen for static. Lightning detectors can be used.

28 Blast Site Safety-Loading Electrical Storms Surface-During the progress and approach of an electrical storm, all blasting operations shall cease. Underground-Electrical blasting operations capable of being initiated by lightning shall be suspended and miners withdrawn from the blast area until safe to return. All miners shall be evacuated from the blast area until the storm has passed. Bad Weather

29 Blast Site Safety-Loading Electric Detonators Check Continuity of each detonator prior to stemming and circuit resistance prior to connection to the power source. Only use approved BLASTER s Galvanometer and BLASTER s multimeter to check electric detonators and circuits.

30 Blast Site Safety-Loading E*Star Electronic Detonators: Internal shunting by protective devises contained in the E*Star detonator replaces the need for an exterior mechanical means of shunting.

31 Blast Site Safety- Loading Non-Electric Detonators Have a second qualified person verify all non-electric connections.

32 Blast Site Safety-Loading Lead Detonator Connection Once the Lead detonator is connected, the lead lines/wires must be manually unreeled.

33 VTCA Safety Seminars ELEMENTS OF BLAST AREA SECURITY CLEARING COMMUNICATING GUARDING CONTROLLING BLAST SHELTER SIGNALLING

34 Blast Area Safety-Clearing 30 CFR 56/57.630(f) Ample time shall be given to allow all miners to be evacuated from the blast area.

35 Blast Area Safety-Clearing There shall be no connection to the power source or attaching an initiating device to the blast until all miners have left the blast area.

36 VTCA Safety Seminars BLAST AREA SAFETY Guarding Assignments Locations Safety Equipment Protection against flyrock Orders Duties Release of Duties

37 VTCA Safety Seminars BLAST AREA SAFETY Communicating Guard/Blaster Communication Devices Guard Communication Instructions Notice of Breach Understanding of the Blasting Signals

38 BLAST AREA SAFETY 30 CFR 56/ (f) (3) All access routes to the blast area shall be GUARDED, or barricaded to prevent the passage of persons or vehicles. VTCA Safety Seminars

39 VTCA Safety Seminars Guarding and Guard Points 2-Lane Public Highway Point D Highway Control Point Point A Blast Site Point E Highway Control Point Point B Ramp Control Point Mine Haul Road-Up Ramp Ramp Control Point Point C Mine Haul Road-Down Ramp

40 Blast Area Safety-Clearing the Blast Area The blaster shall verify the blast area is clear. Double check to be sure all miners and equipment are clear. Are access points guarded?

41 Blast Area Safety-Blast Shelter The blaster, and all other miners in the blast area, shall be protected by a blasting shelter. What is a proper blasting shelter? Pictur?

42 Blast Area Safety-Blast Shelter If you have any question about what type of blasting shelter to use or what is proper cover, ASK BEFORE YOU USE IT.

43 VTCA Safety Seminars Best Location for Shelter? Blaster Protective Shelter-Discussion Locations PIT FLOOR G F E Face H I SHOT Upper Bench Lower Bench A B C D Two Bench Mine (BH= 50 ft)

44 Blast Area Safety Wireless Remote Firing Device

45 VTCA Safety Seminars BLAST AREA SAFETY Blasting Signals Audible Time Schedule Posted

46 BLAST AREA SAFETY Blasting Signals PRE BLAST Audible First Warning Time before detonation? 3 min. prior Signal Type 1 min. siren 30 sec. Silence 1 min. siren 30 sec. BLAST! VTCA Safety Seminars

47 Blast Area (MSHA) Gases? VTCA Safety Seminars Carbon Monoxide (CO) Colorless/Odorless Cause??? Oxides of Nitrogen (No x ) Yellow-Brown- Red? Cause???

48 Blast Area Safety-Post Blast/ Fumes Fumes are Toxic. Fumes shall be allowed to dissipate prior to re-entry into the blast area.

49 Blast Area Safety-Post Blast Exam A Post Blast Exam shall be performed addressing potential blasting hazards. This exam shall be conducted prior to work being able to resume in the blast area.

50 Blast Area Safety-Post Blast BLAST AREA SAFETY Blasting Signals POSTBLAST Audible Means no Misfires, miners may return to the work area Signal Type (EXAMPLE) 30 seconds all clear

51 Blast Area Safety-Post Blast All Clear An All Clear Signal shall be given once the post blast exam has been completed and there are no dangers present.

52 Blast Area Safety-Misfire Procedures What is a Misfire? The complete or partial failure of explosives to detonate as planned.

53 Blast Area Safety-Misfire Procedures Cause for Misfires? Human Error Hurrying Holes not connected Not measuring column rise Product Failure Age Uncoupling Defective Wrong Application Not used according to manufacturer s instructions. Anything Else?

54 Blast Site Safety-Is it a Misfire? If you push the button on the firing device and the shot does not detonate, is this a misfire? Answer: YES. Misfire procedures must be followed.

55 Blast Area Safety-Is it a Misfire? If you forget to connect the last two holes into the blast round, is this a misfire? YES. Misfire procedures must be followed.

56 Blast Area Safety-Misfire Procedures What are the misfire procedures? Before entering the blast area: The power source must be disconnected from the blast round. The firing line must be shunted, if using electric.

57 Blast Area Safety-Misfire Procedures What are the misfire procedures? 30 CFR Misfire waiting period. When a misfire is suspected, persons shall not enter the blast area-- (a) For 30 minutes if safety fuse and blasting caps are used; or (b) For 15 minutes if any other type detonators are used.

58 Blast Area Safety-Misfire Procedures What are the misfire procedures? Defer to State Regulation Clear area for 15 min. BIC, Pit Foreman, or Plant Manager contact: Discuss proper procedures to approach/remove misfire

59 Blast Area Safety-Misfire Procedures What are the misfire procedures? When a misfire cannot be disposed of safely, each approach to the misfire area shall be posted/blocked to prohibit entry into this area. Only work necessary to remove the misfire hazards shall be permitted in the area.

60 VTCA Safety Seminars Flyrock (IME SLP #12) Definition Rocks propelled by the force of an explosion beyond the blast area.

61 FLYROCK Blast Area Definition (MSHA) Flying Material? Rock Shot Rock Rock on the surface of a Shot Stemming Ejection Earth Overburden Mud Seams Ice Man-made things such as steel, concrete, etc This piece of rock was flyrock

62 FLYROCK Major Causes DELAYING ROCK MOVEMENT RELIEF OVERLOADING MISFIRES

63 FLYROCK Flyrock OVERLOADING Insufficient Stemming Prevention???

64 FLYROCK Flyrock OVERLOADING Insufficient Stemming Prevention Adequate Stemming for Charge Diameter and Shot Relief

65 FLYROCK Flyrock OVERLOADING Insufficient Burden Prevention Adequate Burden for Charge Diameter Decoupled Charge Don t Charge or Charge only bottom

66 VTCA Safety Seminars Blasting Safety Questions

Oral Exam Explosives

Oral Exam Explosives 62 What is the only kind of explosive that can be used in an underground coal mine? 63 Permissible explosives and permissible blasting devices. 64 How must a permissible explosive