The odor detection threshold is the lowest concentration of a certain odor compound that is perceivable by the human sense of smell.The threshold of a chemical compound is determined in part by its shape, polarity, partial charges, and molecular mass.The olfactory mechanisms responsible for a compound's different detection threshold is not well understood. Odor Threshold Determinations Of 53 Odorant Chemicals In order to assist in assessing potential odor problems arising from chemical manufacturing operations, the odor thresholds of 53 commercially important odorant chemicals have been determined using a standardized and defined procedure. Anhydrous ammonia, Aqua ammonia, Aqueous ammonia [Note: Often used in an aqueous solution.] CAS Registry No. Odor threshold of ammonia gas. Threshold Limit Values (TLV) and Immediately Dangerous to Life and Health (IDLH) values TLV TLV Substance TWA STEL IDLH TLV TLV Substance TWA STEL IDLH Acetaldehyde - 25C 2,000 Acetic Acid 10 15 50 Acetone 500 750 2,500 Acetonitirle 20 - 500 Acrolein - 0.1C 2 Acrylonitrile 2 - 85 Ammonia 25 35 300 Arsine 0.05 - 3 Benzene 0.5 2.5 500 Isobutylmethylpyrazine; 2-Isobutyl-3-methylpyrazine; 35-130 Colorless gas with a pungent, suffocating odor. Standards Ammonia refrigeration is addressed in OSHA standards for general industry. It plays a role in how your page is seen by search engine crawlers, and how it appears in SERPs ammonia level was 32 ppm for only 7 d or 10 ppm or less for 28 d. Therefore, our data suggest that for mice housed in IVC, which have the potential for 24-h exposure to ammonia for days or weeks at a time, intracage ammonia levels should remain below 25 ppm.” (reference: Vogelweid C.M. Ammonia is one of the most widely produced and utilized chemicals in the U.S., and while numerous lab studies have been undertaken, there is no consensus on the odor threshold. An average person detects ammonia by odor at around 17 ppm. ODOR THRESHOLD = 5 ppm Odor thresholds vary greatly. Ammonia's odor threshold is sufficiently low to acutely provide adequate warning of its presence (odor threshold = … He would much rather be normal. Reasons for Citation Ammonia is on the Right to Know Hazardous Substance List because it is cited by OSHA, ACGIH, DOT, NIOSH, DEP, NFPA and EPA. Ammonia also disperses easily, since is lighter than air (its density is 60% that of air), and does not settle in low lying areas the way hydrogen sulfide and other dense odorous compounds do. Inhalation of ammonia may cause nasopharyngeal and tracheal burns, bronchiolar and alveolar edema, and airway destruction resulting in respiratory distress or failure. most people can taste ammonia in water at levels of about 35 ppm. Although not every organization agrees on the perceptible threshold, OSHA estimates that people begins to smell ammonia gas ranging from 5 to 50 ppm.