# Hydrocyanic acid — OSHA PSM vs EPA RMP: chemical threshold quantities side by side

For Hydrocyanic acid, cas no. is 74-90-8; epa rmp tq (lbs) is 2,500; rmp category is toxic; rmp basis for listing is a, b, recorded from its source on 2026-08-15.

- **Substance:** Hydrocyanic acid _(verified: appears in the quote below)_
- **CAS No.:** 74-90-8 _(verified: appears in the quote below)_
- **EPA RMP TQ (lbs):** 2,500 _(verified: appears in the quote below)_
- **RMP category:** toxic _(our reading, not quoted from the source)_
- **RMP basis for listing:** a, b _(verified: appears in the quote below)_
- **OSHA PSM TQ (lbs):** 1000 _(per osha.gov, not stated by the source above)_

## What the source says

> Hydrocyanic acid | 74-90-8 | 2,500 | a, b

## What osha.gov says

> Hydrogen Cyanide, Anhydrous | 74-90-8 | 1000

Source: https://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.119AppA

## Source

- https://www.ecfr.gov/current/title-40/chapter-I/subchapter-C/part-68/subpart-F/section-68.130
- https://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.119AppA

Last verified: 2026-08-15. Review by: 2027-08-15.
Part of [OSHA PSM vs EPA RMP: chemical threshold quantities side by side](https://referencesource.org/psm-rmp-chemical-threshold-crossref/).