6.2 Shock-Sensitive, Radioactive & Pressurized Containers

Shock-Sensitive, Radioactive & Pressurized Containers

While standard drum handling carries significant risk, encountering specialized or highly hazardous containers escalates the danger exponentially. HAZWOPER personnel must be trained to recognize these containers and apply specific, highly restrictive handling protocols.

Shock-Sensitive and Potentially Explosive Materials

Certain chemicals become highly unstable over time or when exposed to air, forming shock-sensitive compounds. Common culprits include:

• Ethers and Peroxides: Old ethers can form explosive peroxides, especially if the container has been opened and exposed to oxygen.
• Picric Acid: Normally stored safely under water, picric acid becomes a highly sensitive explosive if it dries out, often forming visible crystals.
• Unvented Containers: Any container with crystalline deposits around the cap, bung, or seams should be assumed to contain shock-sensitive material.

Handling Rule: NEVER move or attempt to open a container suspected of holding shock-sensitive materials. The simple friction of unscrewing a cap can cause detonation. Evacuate the area and call specialized response teams (like local bomb squads or specialized hazmat contractors).

Remote Opening Procedures and Blast Barricades

When a drum is visibly bulging (pressurized) or suspected of containing reactive materials, it must never be opened manually by a worker standing next to it. Remote opening procedures must be employed.

1. Blast Barricades/Shields: A protective barrier is erected between the drum and the operating personnel. This shield is designed to deflect shrapnel and blast pressure in the event of an explosion.
2. Remote De-bungers: Mechanical devices attached to the bung that can be operated via long cables or hydraulic lines from behind the barricade.
3. Pneumatic Spikes: For severely pressurized drums where unscrewing the bung is too dangerous, a pneumatically driven spike can be fired remotely into the top of the drum to safely relieve the pressure.

Radioactive Waste Recognition and Handling

Radioactive materials are sometimes discovered at uncontrolled hazardous waste sites. They might be in specialized lead-lined containers or improperly disposed of in standard drums.

• Detection: Radiation cannot be seen, smelled, or felt. Detection relies entirely on instrumentation, primarily the Geiger-Mueller (GM) survey meter.
• ALARA Principles: All work involving radioactive materials must follow the ALARA concept—As Low As Reasonably Achievable. This is achieved through three primary controls:
  • Time: Minimize the time spent near the radiation source.
  • Distance: Maximize the distance from the source (radiation intensity drops off quickly with distance based on the inverse-square law).
  • Shielding: Place appropriate materials (like lead or concrete) between the worker and the source.

Pressurized Cylinders

Compressed gas cylinders present a dual hazard: the chemical hazard of the gas itself (toxic, flammable, corrosive) and the immense physical hazard of the pressure.

• The Missile Hazard: The weakest point of a cylinder is the valve. If a cylinder falls and the valve shears off, the rapid release of high-pressure gas can propel the heavy steel cylinder like a missile, capable of penetrating concrete walls.
• Handling Rules:
  • Cylinders must ALWAYS be stored and moved in an upright position.
  • They must be securely chained or strapped to a wall, rack, or specialized cart.
  • The valve protection cap must be screwed on tightly whenever the cylinder is not in active use.
  • Never attempt to force open a stuck valve; rely on the manufacturer or specialized contractors.

Laboratory Waste Packs (Lab Packs)

Universities, research facilities, and hospitals generate large numbers of small containers of various chemicals. For disposal, these are often consolidated into Lab Packs.

• The Process: A lab pack involves taking a large, DOT-approved outer drum (usually 55-gallon) and placing smaller, intact containers of compatible chemicals inside.
• Compatibility Sorting: This is the most critical step. Incompatible chemicals (e.g., an acid and a base, or an oxidizer and a flammable) must never be packed in the same drum. If a small container breaks, mixing incompatibles could cause a fire, explosion, or toxic gas release inside the drum.
• Packing Material: The empty space inside the drum is filled with an inert, non-reactive absorbent material, most commonly vermiculite. This cushions the smaller containers to prevent breakage and will absorb the liquid if a leak does occur.

Special Container Risk Mitigation Table