Hello, our friends, colleagues, and fellow blasters,
The first snow in Colorado always brings excitement, beauty, and new opportunities for winter recreation—but it also marks the beginning of heightened hazards in the mountains. Early-season snow accumulation can quickly create unstable layers, leading to potential avalanche conditions that require careful monitoring and professional mitigation.
Petr Explosives Group is actively preparing training classes for both new avalanche blasters and experienced personnel seeking recertification. During our courses, we address critical safety considerations, the unique dangers blasters face, and best practices for conducting these high-risk operations with confidence and competence. These recommendations are gathered to support and educate avalanche professionals as they begin another active season.
As we anticipate substantial snowfall and significant avalanche activity this year, we wish everyone a safe and successful season. Please let us know if this information is helpful to you.
Respectfully,
Petr Explosives Group
Safety Rules and Professional Standards for
Avalanche Blasters
A Complete PETS Guide for Safe, Effective, and Responsible Avalanche Control
Operations
Avalanche control work is one of the most specialized and hazardous operations performed in
winter mountain environments. Blasters must navigate steep terrain, unstable snowpacks, low
temperatures, high winds, and hazardous weather—while handling energetic materials under
pressure. To keep teams, resorts, and the public safe, avalanche blasters must follow strict
procedures, consistent habits, and proven professional standards.
This article provides a complete, logically structured guide to the essential safety procedures
every avalanche blaster must know. These rules help ensure every mission is predictable,
controlled, and compliant with state and federal regulations.
1. Pre-Deployment Preparation
1.1 Terrain Assessment
Before entering avalanche terrain, every
blaster must review:
• Start zones, release areas, and runout
paths
• Terrain traps, cliffs, gullies, and
convex rolls
• Historical problem areas
• Safe travel routes and escape lines
• Safe observation and lookout points
Good terrain awareness prevents accidents
before they occur.
1.2 Avalanche Problem Briefing
Blasters must understand:
• Today’s avalanche problem (wind
slab, storm slab, persistent slab, deep
slab)
• Weak-layer depth and characteristics
• Expected propagation behavior
• Overnight wind transport and loading
• Temperature trends and crust
formation
Explosives are only effective when applied to
the correct weak layer in the correct location.
1.3 Mission Planning
A complete control plan includes:
• Assigned roles (Blaster, Assistant,
Overwatch)
• Shot list and order
• Travel route and escape routes
• Communication plan and radio
channels
• Weather limitations (wind, visibility,
storms)
• Misfire protocol
Petr Explosives Group.Com Page of 1 4 Wednesday, December 10, 2025• Emergency response and evacuation
plan
No control team enters terrain without a fully
reviewed plan.
2. Explosives Handling and Fuse
Management
2.1 Professional Explosives Handling
Blasters must:
• Inspect every charge
• Keep detonators and explosives
separated until final assembly
• Protect explosives from moisture,
impact, and cold shock
• Assemble charges in a consistent,
methodical manner
• Maintain physical control of all
explosives at all times
Discipline and repetition prevent avoidable
mistakes.
2.2 Fuse Burn Rate
Daily fuse test:
• 36 inches ≈ 120 seconds
• 1 inch ≈ 3.3 seconds
Burn rate is affected by:
• Temperature
• Moisture / wet snow
• Wind
• Manufacturing variation
Blasters must set fuse length based on the
actual burn rate—not assumptions.
Fuse time = escape time. Never guess.
Always test.
3. Static Electricity Hazards
Cold, dry, windy conditions—especially
during snowstorms—dramatically increase
the risk of static electricity discharge, which
can unintentionally ignite detonators or
detonating cord.
Static is most dangerous in:
• Dry powder snowstorms
• High winds and blowing snow
• Extremely cold, low-humidity
conditions
• Synthetic clothing layers
• Nylon harnesses, plastic seats, and
certain gloves
3.1 Static Electricity Rules
Blasters must:
• Avoid synthetic base layers that
generate static (prefer wool/cotton)
• Avoid sliding on nylon, plastic, or
foam pads with detonators nearby
• Touch grounded metal before
handling caps or detcord
• Keep gloves on during explosive
handling
• Keep detonators insulated from metal
tools or equipment
• Avoid handling explosives near
running snowmobiles, generators, or
antennas
• Be alert: If you feel a static “snap,”
stop work immediately and re-ground.
Static electricity risk is invisible—but
completely preventable.
4. Charge Placement and Shot
Effectiveness
Blasters must understand:
• Pressure decreases dramatically with
distance
• Weak-layer depth increases effective
standoff distance
• Snow type (soft slab, hard slab, depth
hoar) changes energy transmission
• Elevation reduces explosive
effectiveness
• Suspended charges usually produce
better energy coupling
• Surface charges are less efficient but
sometimes necessary
This is why PETS developed the Avalanche
Explosives Calculator for training: to help
blasters visualize real-world energy
propagation.
Precision—not brute force—creates results.
Petr Explosives Group.Com Page of 2 4 Wednesday, December 10, 20255. Detonating Cord and
Suspended Charges
These techniques require formal, written
Standard Operating Procedures (SOPs)
because of their elevated hazard.
5.1 Detonating Cord SOP
Requirements
SOP must specify:
• Cutting, knotting, and bend radius
limits
• Approved priming methods
• Minimum standoff from personnel
• Static electricity precautions
• Storage and transport protocols
• Post-blast inspection requirements
5.2 Suspended Charge SOP
Requirements
Includes:
• Approved anchor systems (trees, rock
anchors, cable)
• Minimum suspension height
• Load-rated attachment requirements
• Safe retreat path
• Wind limitations
• Misfire procedures for hanging
charges
Only trained, qualified blasters may perform
these operations.
6. Team Conduct and
Communication
6.1 Never Work Alone
Minimum team: 2 blasters
Preferred: 3 (Blaster + Assistant +
Overwatch)
6.2 Radio Communication Standards
Required calls:
• “Team in position”
• “Ready to fire”
• “Firing now”
• “Shot fired”
• “Detonation confirmed”
• “Misfire”
If communication becomes unclear, stop
operations immediately.
7. Photography & Video Rules
To protect safety, professionalism, and
regulatory compliance:
Allowed
• Documenting training
• Misfire investigation photos
• Snowpack or shot-placement
documentation
Prohibited
• Posting videos or photos on social
media
• Recording explosive assembly
• Filming detonators, fuse ends, or
charge construction
• Allowing public observers to take
videos during blasting
All imagery must be approved by operations
leadership.
8. Public Management & Crowd
Safety
Before firing:
• Public must be cleared from all hazard
zones
• All ski runs, trails, and roads must be
closed
• Signs, ropes, or barricades must be in
place
• Coordination with highway patrol or
ski patrol is required
No member of the public may:
• Enter closed terrain
• Approach blasting teams
• Record blasting operations from
within hazard distances
Areas reopen only after detonation
confirmation and safety clearance.
9. Misfire Procedures
Petr Explosives Group.Com Page of 3 4 Wednesday, December 10, 2025A misfire is a high-risk event requiring strict
protocol.
9.1 Immediate Actions
• Stop all movement
• Announce: “Misfire — hold
positions”
• Wait minimum 1 hour (required)
• Do not approach the shot
9.2 Documentation
Record:
• GPS location
• Charge type, weight, fuse length
• Snow and terrain observations
9.3 Reporting
• Inform explosives supervisor
• Mark for spring retrieval
• ATF Form 5400.5 must be filed if
unrecovered at season’s end
No early returns. No exceptions.
10. Spring Retrieval & Counter-
Detonation
Spring melt requires:
• Visiting all documented misfire
locations
• Approaching cautiously
• Never moving unstable remnants
• Counter-detonating when necessary
• Logging all recoveries/destructions
• Closing ATF lost/stolen reports
Every charge deployed must be accounted for.
11. Emergency Response
11.1 If a Blaster Is Injured
• Stop blasting
• Ensure area is safe
• Radio: “Blaster injured — need
assistance”
• Give location and assessment
• Provide first aid & hypothermia
protection
• Evacuate using safest method
11.2 If a Blaster Is Missing or Buried
• Initiate beacon search
• Identify last known point
• RECCO/probe if needed
• Suspend all blasting
• Notify command immediately
11.3 If a Blaster Dies
• Secure area
• Notify leadership, law enforcement,
coroner, OSHA, ATF
• Preserve scene unless unsafe
• Document everything
• Provide structured debrief and mental
health support for team
12. Core Principles of Professional Avalanche Blasting
• Never work alone
• Static electricity is a real ignition hazard — manage it proactively
• Safety first, speed second
• Every shot must have purpose
• Every explosive must be accounted for
• Respect the mountain, respect the charges, respect the team
When blasters understand why these procedures exist—not just what to do—avalanche control
becomes significantly safer, more predictable, and more effective
