Hydrogen Cyanide (HCN) Detectors

Which hydrogen cyanide (HCN) detector should you buy in 2026?

Short answer: For hydrogen cyanide, use a dedicated HCN monitor such as the Forensics HCN Detector (0-50 ppm, NIST) — for fumigation, electroplating and fire overhaul, where HCN is acutely toxic and outside the 4-gas set.

Hydrogen cyanide (HCN) is an acutely toxic gas that interferes with the body's use of oxygen. It is a hazard in fumigation, electroplating, some chemical processes, and fire overhaul (burning plastics and foams release HCN). It needs a dedicated detector with low alarm set points.

This is a gas-type collection under the Gas Detectors hub. Match the gas to the right form factor: Portable Gas Detectors for carried checks, Personal & Wearable Gas Detectors for single-worker exposure, Fixed Gas Detection Systems for continuous plant monitoring, Area & Transportable Gas Monitors for job-site zones, and Gas Leak Detectors to pinpoint a leak source.

Detectors in this collection

This collection gathers HCN instruments. The Forensics HCN Detector reads 0-50 ppm with NIST calibration and triple alarms. For the four atmospheric gases alongside HCN, pair it with a unit from Portable Gas Detectors.

Editor’s pick — a NIST-calibrated handheld HCN monitor
The Forensics HCN Detector pairs a low 0-50 ppm range with NIST calibration and triple alarms — matched to HCN’s acute toxicity. As an Amazon Associate, WC Safety earns from qualifying purchases.

CHECK PRICES ON AMAZON →

How to choose a hydrogen cyanide detector

Low alarms for an acute toxin

HCN is dangerous at low ppm, so set low alarm points and bump-test regularly.

Know the sources

Fumigation, electroplating, chemical processes and fire overhaul (HCN from burning plastics/foams) are the main HCN exposures.

Placement

Hydrogen cyanide is lighter than air, so it rises and disperses upward, but acute releases are dangerous throughout a space.

Hydrogen Cyanide (HCN) hazard, exposure limits & placement

OSHA sets a PEL around 10 ppm (with skin notation) for hydrogen cyanide, and ACGIH lists a low short-term limit. HCN is acutely toxic, so low alarm set points and reliable detection are essential. Confirm current limits with OSHA's annotated PEL tables.

Frequently asked questions

What detects hydrogen cyanide?

A dedicated HCN detector with an electrochemical sensor — a standard 4-gas monitor does not cover HCN.

Where is HCN detection needed?

Fumigation operations, electroplating shops, some chemical manufacturing, and fire overhaul, where burning plastics and foams release HCN.

What is the OSHA limit for HCN?

Around 10 ppm (skin) per the OSHA PEL, with a low ACGIH short-term limit. HCN is acutely toxic.

Why is HCN so dangerous?

Hydrogen cyanide blocks the body's ability to use oxygen and is lethal at relatively low concentrations, which is why dedicated detection and low alarms matter.

Is HCN released in fires?

Yes — burning plastics, foams and synthetic materials release HCN, making it a key fire-overhaul hazard alongside carbon monoxide.

Do HCN sensors need calibration?

Yes — bump-test with HCN calibration gas and recalibrate on schedule; electrochemical HCN sensors are consumables.

Can I use it for confined-space entry?

HCN is one hazard; entry also needs O2, combustible and toxic testing with a portable 4-gas instrument.

Is HCN heavier or lighter than air?

Slightly lighter than air, but acute releases are dangerous throughout a space, so detection and ventilation both matter.

Portable or fixed HCN detection?

Handheld units cover surveys and exposure; fixed HCN detection exists for process areas. See Fixed Gas Detection Systems.

What does the Forensics HCN Detector cover?

The Forensics HCN Detector reads 0-50 ppm HCN with NIST calibration and triple alarms.