Hydrogen Cyanide (HCN)
Quick Reference
What is HCN?
HCN is a highly toxic and flammable gas that is used to synthesize cyanide salts for the mining and metal plating industries, synthesize plastics and synthetic fibres, and for specialized pest control. It has a characteristic “almond” flavor. It can be stored and transported in three main ways: 1) as a compressed gas (UN 1051 ERG 117P, 2) dissolved in water (UN 1613, ERG 154) and 3) as an aqueous solution contained in an absorbent material (UN1614, ERG 152). Usually transported in high-pressure, rubber lined railcars but may also be transported in smaller containers by semi-truck. Also released in structure fires.
Crew Safety
- Staging/Perimeter
- Refer to specific UN number and reference ERG for staging requirements.
- Additional Resources
- A HAZMAT or on-site emergency response team.
- PPE requirements
- SCBA plus chemical protective clothing (no fire) or structural fire gear (fire).
- After decontamination, gown, gloves and eye shield should be worn.
- Safely initiating patient contact
- Patients to be brought to paramedics in a safe location. Gross decon prior to paramedic contact.
Effect on the Patient
Cyanogenic compounds bind to cytochrome-c-oxidase and interrupt normal aerobic respiration, causing cellular hypoxia. Rapid alteration in level of consciousness may occur, including loss of consciousness and seizures. Tachycardia and other dysrhythmias may occur. Normal SpO2. Irritation of upper airway may be present.
Patient Decontamination
Remove contaminated clothing, flush exposed skin with water/soap. If eyes exposed or irritated flush for 15 minutes. Contaminated clothing not to be transported. If exposure occurred due to a house fire, clothing should be removed from the patient followed with washing of soot/smoke with mild soap and water.
Patient Treatment
* High flow O2, support ABC’s and treat as per BCEHS CPGs.
* Antidote is hydroxocobalamin, prioritize transport to hospital for treatment.
Safe Transfer of Care
Patient should be decontaminated and clothing removed prior to transferring care/entering hospital.
Paramedic and Equipment Decontamination
Provided patient was decontaminated prior to transport no special precautions are required. If decontamination was not adequate prior to transport, open all doors and ventilate the ambulance.
Quick Access Resources
DPIC Monograph
Paramedic Specialist Safety Data Sheet
No SDS available.
Emergency Response Guidebook
Revision History
| Version | Date | Changes | Author |
|---|---|---|---|
| 1.0 | 2026-05-01 | Initial version | Clinical Hub |