# CYCLOPROPANE — NFPA 704 fire diamond ratings by chemical

For CYCLOPROPANE, cas number is 75-19-4; health (blue) is 1; flammability (red) is 4; instability (yellow) is 0; what the rating means is Health | 1 | Can cause significant irritation. | Flammability | 4 | Burns readily. Rapidly or completely vaporizes at atmospheric pressure and normal ambient temperature. | Instability | 0 | Normally stable, even under fire conditions. | Special | | |, verified against its source on 2026-08-06.

- **Chemical:** CYCLOPROPANE _(verified: appears in the quote below)_
- **CAS number:** 75-19-4 _(verified: appears in the quote below)_
- **Health (blue):** 1 _(verified: appears in the quote below)_
- **Flammability (red):** 4 _(verified: appears in the quote below)_
- **Instability (yellow):** 0 _(verified: appears in the quote below)_
- **What the rating means:** Health | 1 | Can cause significant irritation. | Flammability | 4 | Burns readily. Rapidly or completely vaporizes at atmospheric pressure and normal ambient temperature. | Instability | 0 | Normally stable, even under fire conditions. | Special | | | _(verified: appears in the quote below)_

## What the source says

> Health | 1 | Can cause significant irritation. | Flammability | 4 | Burns readily. Rapidly or completely vaporizes at atmospheric pressure and normal ambient temperature. | Instability | 0 | Normally stable, even under fire conditions. | Special | | |

## Source

- https://cameochemicals.noaa.gov/chemical/500

Last verified: 2026-08-06. Review by: 2028-08-05.
Part of [NFPA 704 fire diamond ratings by chemical](https://referencesource.org/nfpa-704-hazard-ratings/).