Ammonia Release at a Cold-Storage Warehouse

Establish command upwind and uphill of the release, and immediately isolate the area. Do not send a crew in structural firefighting PPE: ammonia is corrosive to skin, eyes, and airways, and structural turnout gear with SCBA does not provide the needed chemical protection against a dense vapour cloud. The rescue decision depends on whether a viable rescue can be made without adding to the casualty count. With no chemical-protective suits and no backup team, an unprotected entry would likely produce more collapsed workers and contaminate rescuers. I would request the hazmat team, EMS, police, and the plant's emergency coordinator immediately, and ask the plant manager for the isolation valve location, wind direction, and any fixed monitoring. If the workers are conscious and can move, direct them to a safe upwind area without entering the cloud. If they are unconscious and the vapour is dense at the door, rescue must wait for properly equipped personnel unless a trained crew with appropriate CPC and SCBA can reach them with a backup and decontamination plan. The life-safety priority is to prevent the emergency from expanding.

Use the visible vapour cloud, air monitoring, and wind direction to set an initial hot zone that keeps all unprotected people out. The warm zone is the controlled area for decontamination and equipment staging, and the cold zone is command, EMS, and the public. Because the vapour is drifting toward a residential street, the hot zone must be upwind and must not be placed below the loading dock, where ammonia vapour may collect. Structural PPE with SCBA is not acceptable for entry into the hot zone; the hazmat team will use appropriate chemical-protective clothing and SCBA. Decontamination must be set up before any rescue or entry, with a hose line or decon shower, runoff control, and a plan for removing and bagging contaminated clothing. Firefighters must not eat, drink, or remove PPE in the warm zone. The pumper can support a water fog to knock down vapour only if it does not spread contaminated runoff or push vapour toward people. All actions require air monitoring and a safety officer.

In the first 15 minutes, notify the plant, hazmat, EMS, police, the local environment agency, and the emergency management office. Use police to evacuate or shelter the residential street downwind, depending on the vapour concentration and time available; for a corrosive gas release, moving people upwind or indoors with windows and ventilation closed is usually safer than allowing them to pass through the cloud. Establish a media and public information point only after the operational sectors are set. Request additional pumping capacity and lighting if the incident extends into darkness. The plant manager should provide the safety data sheet, system diagram, and isolation valve information, but do not accept a verbal assurance that the release is small. The first 15 minutes should also include a clear record of decisions, times, and notifications, because the incident may become a multi-agency investigation. The incident commander must resist pressure to send untrained crews into the hot zone simply because workers are visible.