The exposure limit for ammonia varies by region and agency, but here are some of the most common limits:

 The exposure limit for ammonia varies by region and agency, but here are some of the most common limits:

OSHA PEL

The permissible exposure limit (PEL) for ammonia in the United States is 50 parts per million (ppm) for an 8-hour time-weighted average (TWA). 

NIOSH REL

The recommended exposure limit (REL) for ammonia in the United States is 25 ppm for an 8-hour TWA. 

NIOSH IDLH

The immediately dangerous to life or health (IDLH) concentration for ammonia in the United States is 300 ppm. 

ACGIH TLV

The threshold limit value (TLV) for ammonia is 25 ppm for an 8-hour TWA and 35 ppm for a 15-minute short-term exposure limit (STEL). 

Ammonia is a colorless gas with a strong, irritating odor. It can be found in a variety of forms, including anhydrous ammonia, ammonium hydroxide, and household cleaners. Exposure to ammonia can cause burns to the skin, eyes, mouth, and lungs. 

To protect workers from ammonia exposure, workplaces should: 

Have exposure monitoring programs in place

Ensure adequate ventilation

Provide appropriate personal protective equipment (PPE), such as respirators

Have safety protocols in place

Provide safety training to employees