The Definition of Ammonia Exposure

Definition of Ammonia Exposure

Ammonia exposure occurs when workers breathe ammonia gas or have skin or eye contact with anhydrous ammonia or ammonia solutions. Ammonia is a colorless, corrosive gas with a sharp, pungent odor, widely used as an industrial refrigerant in food and beverage processing and cold storage, as an agricultural fertilizer, and in chemical manufacturing. It reacts with moisture in the body to burn the eyes, skin and airways, and high concentrations can cause fatal lung damage. Liquid anhydrous ammonia can also cause frostbite-like cold burns on contact.

Key Facts About Ammonia Exposure

• OSHA PEL: 50 ppm as an 8-hour TWA.
• NIOSH REL: 25 ppm TWA and 35 ppm short-term exposure limit; IDLH is 300 ppm.
• Most people smell ammonia at levels well below the PEL, but odor is not a reliable way to judge how much is present.
• Facilities with more than 10,000 pounds of anhydrous ammonia fall under OSHA Process Safety Management (1910.119) and EPA's Risk Management Program.
• OSHA 1910.111 sets requirements for storing and handling anhydrous ammonia.

Example of Ammonia Exposure

At a refrigerated warehouse, a fixed ammonia detector in the engine room alarms during a valve repair. Workers evacuate upwind to the muster point, emergency ventilation starts automatically, and the facility's trained hazmat team enters wearing SCBA and chemical-protective suits to isolate the leak.

How to Prevent and Respond to Ammonia Exposure

• Install fixed gas detection with alarms in machinery rooms and near likely release points.
• Maintain systems through mechanical integrity inspections, especially valves, seals and relief devices.
• Train workers on the safety data sheet, alarms and evacuation routes.
• Provide eyewash stations and safety showers near ammonia equipment.
• For skin or eye contact, flush with water immediately for at least 15 minutes and get medical care.
• Leave leak response to trained responders under the site's emergency response plan and HAZWOPER rules.

Related Terms

• Chemical Hazard
• Immediately Dangerous to Life or Health (IDLH)
• Respiratory Protection
• Acute Exposure

Frequently Asked Questions: Ammonia Exposure

What are the symptoms of ammonia exposure?

Low levels cause eye, nose and throat irritation, coughing and watery eyes. Higher levels cause burning of the eyes and skin, chest tightness, difficulty breathing and fluid in the lungs, which can be delayed. Severe exposure can cause blindness, lung damage or death.

Can an air-purifying respirator be used for ammonia?

A respirator with ammonia or methylamine cartridges may be used only when concentrations are known, oxygen is adequate, and levels are within the respirator's protection factor and below IDLH. Leak response and unknown concentrations require SCBA.

Which industries have the highest ammonia exposure risk?

Food and beverage processing, cold storage warehouses, ice rinks, fertilizer production and distribution, agriculture and chemical manufacturing have the highest risk because they store or circulate large amounts of ammonia.