Reference Source

AMMONIA, ANHYDROUS

For AMMONIA, ANHYDROUS, cas number is 7664-41-7; health (blue) is 3; flammability (red) is 1; instability (yellow) is 0; what the rating means is Health | 3 | Can cause serious or permanent injury. | Flammability | 1 | Must be preheated before ignition can occur. | Instability | 0 | Normally stable, even under fire conditions. | Special | | | Note: The Refrigeration System Classification section of the International Mechanical Code requires a value of 3 for the red quadrant (flammability hazard) for indoor ammonia refrigeration equipment, verified against its source on 2026-08-06.

Chemical
AMMONIA, ANHYDROUS verified
CAS number
7664-41-7 verified
Health (blue)
3 verified
Flammability (red)
1 verified
Instability (yellow)
0 verified
What the rating means
Health | 3 | Can cause serious or permanent injury. | Flammability | 1 | Must be preheated before ignition can occur. | Instability | 0 | Normally stable, even under fire conditions. | Special | | | Note: The Refrigeration System Classification section of the International Mechanical Code requires a value of 3 for the red quadrant (flammability hazard) for indoor ammonia refrigeration equipment. verified
Sourcecameochemicals.noaa.gov
Verified2026-08-06
Review by2028-08-05
DatasetNFPA 704 fire diamond ratings by chemical

What the source says

Health | 3 | Can cause serious or permanent injury. | Flammability | 1 | Must be preheated before ignition can occur. | Instability | 0 | Normally stable, even under fire conditions. | Special | | | Note: The Refrigeration System Classification section of the International Mechanical Code requires a value of 3 for the red quadrant (flammability hazard) for indoor ammonia refrigeration equipment.

cameochemicals.noaa.gov, retrieved 2026-08-06

Source

Last verified against source: 2026-08-06. Due for re-check by 2028-08-05. This page as Markdown · OKF bundle · full dataset as JSON.