Non-Electric Demolition and Blasting Procedures

• PETN (White core)
• ROX (Pink core)
• HMX (White core)

Procedures and Safety Protocols

The blasting cap is the most sensitive portion of any explosive train. Because it serves as the initiator, it must be handled with extreme care.

Inspection and Preparation

Before use, every blasting cap must undergo a rigorous inspection. Technicians must check for:

1. Obstructions in the tube or cap.
2. Dents in the metal casing.
3. Moisture, which can cause a failure to initiate.

When preparing a cap, a crimper is used to secure the cap to the fuse. Proper crimping ensures a secure connection that won't slip during handling or initiation.

Time Fuse Preparation and the "Test Burn"

Because the burn rate of a time fuse can vary based on environmental conditions, it is mandatory to determine the specific Burn Rate (BR) before starting the operation. This is done via a "test burn," which must be conducted at least 50 feet downwind from the main site.

Once the burn rate is known, the required amount of fuse is calculated using the Safe Separation Time (SST) and the Burn Time (BT). To prevent the time fuse from curling or burning through itself, it should be weighed down with dirt or sand—never rocks—at a distance of $2''$to$18''$ from each end.

Priming Techniques

Priming is the process of placing the initiator into the main explosive charge. A priming spike is often used to create a small pocket in the explosive material to seat the cap.

CRITICAL SAFETY RULE: Never force a blasting cap into an explosive charge. If the cap does not seat easily, the pocket must be re-evaluated.

Different explosives require different priming methods:

• Dynamite: Can be primed via end priming (placing the cap at the end of the stick) or lacing (using DetCord).
• C-4 and Semtex: These plastic explosives can be primed using end priming, side priming, or by using DetCord knots such as the Hasty whip, Uli knot, or Double overhand knot.
• Cast Boosters: These are typically primed by inserting DetCord through a pre-drilled priming hole or by using dual priming (inserting two blasting caps).

Final Ignition and Alerts

Before any ignition occurs, the technician must provide three clear, audible "FIRE IN THE HOLE" alerts to ensure all personnel are clear of the blast area.

Misfire Management

A misfire occurs when the explosive train fails to initiate as intended. Because the cause of the failure is unknown, misfires must be treated as highly dangerous.

Summary of Explosive Characteristics

Understanding the distinction between different explosive types is vital for selecting the correct initiation method.

• High Explosives: These detonate at velocities above $3300 \text{ fps}$ and do not require a container to function.
• Low Explosives: These burn (deflagrate) at velocities below $3300 \text{ fps}$ and generally require confinement to build pressure for an explosion.
• Blasting Agents: These are not cap-sensitive and require a booster to initiate (e.g., ANFO).

STUDY TIP: Remember the "SAD" acronym for Render Safe Procedures: Separate (interrupt the train), Analyze (the fuzing), and Disassemble (the device).