---
title: "Methylene-bis-(4-cyclohexylisocyanate) (5124-30-1)"
url: https://analyt-mtc.com/tools/hazard-search/methylene-bis-4-cyclohexylisocyanate-5124-30-1/
lang: en
alternates:
  en: https://analyt-mtc.com/tools/hazard-search/methylene-bis-4-cyclohexylisocyanate-5124-30-1/
  de: https://analyt-mtc.com/de/tools/gefahrstoffsuche/methylene-bis-4-cyclohexylisocyanate-5124-30-1/
---

Hazard search

# Methylene-bis-(4-cyclohexylisocyanate)

CAS number

5124-30-1

Also known as

1,1'-Methylenebis(4-isocyanatocyclohexane) · 4,4'-Methylene-bis(cyclohexyl isocyanate) · 4,4'-methylenedicyclohexyl diisocyanate · HMDI · Hydrogenated MDI · Methylene-bis-(4-cyclohexylisocyanate) (isocyanates, total)

## UK workplace exposure limits

| Limit | Value | Applies to |
| --- | --- | --- |
| 8-hour TWA | 0.02 mg/m³ |  |
| 15-minute STEL | 0.07 mg/m³ |  |

### Notations

-   Sen: can cause sensitisation

## Sampling methods

| Method | Sampling | Medium | Analysis | Part numbers |
| --- | --- | --- | --- | --- |
| **MDHS 25/4** / Organic Isocyanates in air (aerosols) by HPLC -EC / [Method document (opens in a new tab)](https://www.hse.gov.uk/pubns/mdhs/pdfs/mdhs25-4.pdf) | Active (pump) | Midget impinger & coated glass fibre filter |  | [225-36-4](https://analyt-mtc.com/catalog/product/skc-impingers/#part-225-36-4) / [225-22](https://analyt-mtc.com/catalog/product/biosampler/#part-225-22) |
| **MDHS 25/4** / Organic Isocyanates in air (vapours only) by HPLC -EC / [Method document (opens in a new tab)](https://www.hse.gov.uk/pubns/mdhs/pdfs/mdhs25-4.pdf) | Active (pump) | Stainless Steel IOM with coated glass fibre filter |  | [225-79A](https://analyt-mtc.com/catalog/product/iom-sampler/#part-225-79a) |
| **MDHS 25/4** / Organic Isocyanates in air (aerosols per Appendix 2) by HPLC -EC / [Method document (opens in a new tab)](https://www.hse.gov.uk/pubns/mdhs/pdfs/mdhs25-4.pdf) | Active (pump) | Stainless Steel IOM with coated glass fibre filter(s) |  | [225-79A](https://analyt-mtc.com/catalog/product/iom-sampler/#part-225-79a) |
| **NIOSH 5525** / Isocyanates, total (MAP) (Aerosols of aromatic isocyanates >2 µm) by HPLC -UV/FD / [Method document (opens in a new tab)](https://www.cdc.gov/niosh/docs/2003-154/pdfs/5525.pdf) | Active (pump) | Impinger |  | [225-36-1](https://analyt-mtc.com/catalog/product/skc-impingers/#part-225-36-1) / [225-22](https://analyt-mtc.com/catalog/product/biosampler/#part-225-22) |
| **NIOSH 5525** / Isocyanates, total (MAP) (Aerosols of aromatic isocyanates) by HPLC -UV/FD / [Method document (opens in a new tab)](https://www.cdc.gov/niosh/docs/2003-154/pdfs/5525.pdf) | Active (pump) | Impinger with coated glass fibre filter | HPLC-UV | [225-7](https://analyt-mtc.com/catalog/product/glass-fibre-depth-filters/#part-225-7) / [225-4](https://analyt-mtc.com/catalog/product/sureseal-cassette-blanks/#part-225-4) / [225-27](https://analyt-mtc.com/catalog/product/disposable-parallel-particle-impactors/#part-225-27) / [225-36-1](https://analyt-mtc.com/catalog/product/skc-impingers/#part-225-36-1) / [225-22](https://analyt-mtc.com/catalog/product/biosampler/#part-225-22) / [225-702](https://analyt-mtc.com/catalog/product/button-sampler/#part-225-702) / [225-76A](https://analyt-mtc.com/catalog/product/iom-sampler/#part-225-76a) |
| **NIOSH 5525** / Isocyanates, total (MAP) (Vapour only) by HPLC -UV/FD / [Method document (opens in a new tab)](https://www.cdc.gov/niosh/docs/2003-154/pdfs/5525.pdf) | Active (pump) | Stainless steel IOM with coated glass fibre filter |  | [225-76A](https://analyt-mtc.com/catalog/product/iom-sampler/#part-225-76a) / [225-702](https://analyt-mtc.com/catalog/product/button-sampler/#part-225-702) |
| **OSHA 5002** / Organic Vapour Sampling Group 3-diisocyanates- by UHPLC-FD / [Method document (opens in a new tab)](https://www.osha.gov/sites/default/files/methods/osha-5002.pdf) | Active (pump) | Glass fibre filter & support pad in open-face cassette | HPLC-UV or HPLC-FD | [225-9002](https://analyt-mtc.com/catalog/product/skc-coated-treated-filters/#part-225-9002) / [225-9013](https://analyt-mtc.com/catalog/product/skc-coated-treated-filters/#part-225-9013) |
| **OSHA 5002** / Organic Vapour Sampling Group 3 by UHPLC-FLR / [Method document (opens in a new tab)](https://www.osha.gov/sites/default/files/methods/osha-5002.pdf) | Active (pump) | Open-face cassette with Glass Fibre Filter & support pad (page 2 of method) |  | [225-3250](https://analyt-mtc.com/catalog/product/sureseal-cassette-blanks/#part-225-3250) / [225-7](https://analyt-mtc.com/catalog/product/glass-fibre-depth-filters/#part-225-7) / [225-27](https://analyt-mtc.com/catalog/product/disposable-parallel-particle-impactors/#part-225-27) |

Methods and limits as published by their agencies and summarised by SKC; check the current method and the limit that applies to you before sampling.

Source: [SKC Ltd (UK), Hazard Search, used with SKC's permission (opens in a new tab)](https://www.skcltd.com/hazard-search.html); [SKC Inc. (USA), Sampling Guides, used with SKC's permission (opens in a new tab)](https://international.skcinc.com/sampling-guides/)