# Methyl Isocyanate — OSHA PSM vs EPA RMP: chemical threshold quantities side by side

For Methyl Isocyanate, cas no. is 624-83-9; osha psm tq (lbs) is 250, verified against its source on 2026-08-15.

- **Substance:** Methyl Isocyanate _(verified: appears in the quote below)_
- **CAS No.:** 624-83-9 _(verified: appears in the quote below)_
- **OSHA PSM TQ (lbs):** 250 _(verified: appears in the quote below)_
- **EPA RMP TQ (lbs):** 10,000 _(per ecfr.gov, not stated by the source above)_
- **RMP category:** toxic _(per ecfr.gov, not stated by the source above)_
- **RMP basis for listing:** a, b _(per ecfr.gov, not stated by the source above)_

## What the source says

> Methyl Isocyanate | 624-83-9 | 250

## What ecfr.gov says

> Methyl isocyanate [Methane, isocyanato-] | 624-83-9 | 10,000 | a, b

Source: https://www.ecfr.gov/current/title-40/chapter-I/subchapter-C/part-68/subpart-F/section-68.130

## Source

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

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/).