On September 11, 2012, 28-year-old Robert Munoz was working at Gibson Winery in Sanger (near Fresno) when a coworker opened the wrong valve, releasing anhydrous ammonia into the room. Munoz was overcome and died; five of his coworkers were also treated for ammonia inhalation.

Just one month later, another ammonia leak sent three workers from Golden State Vintners in Fresno to the hospital.

This checklist, which is drawn from a California Division of Occupational Safety and Health hazard alert, can help you quickly determine whether you're prepared to prevent and respond to such ammonia releases.

Preventing ammonia releases

Wherever anhydrous ammonia refrigeration systems are used, employers should act to prevent ammonia releases by:

• Developing and maintaining a written operational and preventive maintenance program;


• Requiring all refrigeration maintenance personnel and operators to follow written, standard procedures for operating and maintaining the system at safe limits; and


• Ensuring that the ammonia refrigeration system is operated and maintained only by trained and competent personnel.

Preparing workers

Employees who work in facilities where ammonia refrigeration systems are used need to be trained in:

• The hazards of ammonia. Ammonia is corrosive to the skin, eyes, and lungs, and is immediately dangerous to life and health (IDLH) at concentrations of 300 ppm or greater. It can be explosive, and can also react disastrously with some other chemicals by, for example, releasing deadly gases or forming highly hazardous substances.


• How to detect an ammonia release. Ammonia has a strong characteristic odor that can be detected when between 1 and 50 ppm. An ammonia release may also appear as an ammonia cloud, which looks like white fog.


• The symptoms of ammonia exposure. Common symptoms include skin and eye burns, severe throat pain, coughing, and wheezing.


• Emergency escape procedures. Workers must know the proper way to use emergency escape respirators, among other procedures.

Workers should know how to respond to an ammonia release, including how to report the release. They must know how to react appropriately if they:

• Smell ammonia. They should immediately leave the area and notify a supervisor.


• Inhale ammonia. They should immediately move to fresh air and seek medical attention.


• Have skin or eye contact. They should immediately flush the affected area with water for 15 minutes.


• See an ammonia cloud (white fog). They should immediately exit the building or area and move upwind to a designated location.