Overview
EN 27201-2:1994 (ISO 7201-2:1991) - Fire protection: Fire extinguishing media - Halogenated hydrocarbons - Part 2 - is a code of practice for the safe handling and transfer procedures of halon 1211 and halon 1301. The standard provides practical recommendations to reduce emissions to the atmosphere and to protect the health and safety of personnel involved in filling, emptying, transferring and recovering halon from containers and fire-extinguishing equipment.
Key topics and technical requirements
- Scope and definitions
- Covers transfer, filling, refilling, emptying and recovery of halon 1211 and halon 1301.
- Uses the term “halon” to refer specifically to halon 1211 and halon 1301 in this part.
- Health and exposure limits
- Occupational exposure limit: 1000 ppm (8 h TWA).
- Short-term volunteer tests: safe 1-minute exposures reported as 7–10% v/v for halon 1301 and 4–5% v/v for halon 1211; avoid prolonged or higher exposures.
- Decomposition produces corrosive acids (HF, HCl, HBr) and free halogens with a sharp acrid odor - a warning of danger.
- Pressure and equipment safety
- Use dry nitrogen for overpressurization; nitrogen moisture must be very low (≈ 0.006% m/m).
- Nitrogen cylinders require a pressure‑reducing valve, an outlet pressure gauge and a pressure‑relief device (bursting discs not suitable).
- Transfer and recovery rigs must withstand a test pressure of at least twice the anticipated normal working pressure and be leak‑tested regularly.
- Transfer methods
- Nitrogen overpressurization and pumping are described; positive displacement pumps must allow recycle of halon back to supply to prevent overrun.
- Hoses and pipe runs should be short; fittings and valves must be checked for leaks.
- Contamination control and materials
- Avoid mixing halon types (complicates reprocessing).
- Prevent oil, water and moisture ingress (moisture can cause corrosion/hydrolysis).
- Halons are generally inert to common materials, but manufacturers’ data should be consulted.
- Operational controls
- Separate filling/refilling and recovery operations to avoid contamination.
- Receiving containers must be suitable pressure vessels, clearly labelled and not overfilled (weighing recommended).
- Recovered halon must meet ISO 7201-1 specifications before reuse; otherwise reprocess.
Applications and users
- Practical guidance for: fire protection engineers, fire extinguisher service technicians, maintenance teams for fixed halon systems, hazardous-materials handlers, and organizations performing halon recovery and recycling.
- Useful where halon 1211 and halon 1301 are handled: filling facilities, fire‑equipment servicing, decommissioning of halon systems, and environmental compliance programs aimed at minimizing ozone-depleting emissions.
Related standards
Keywords: halon, halon 1211, halon 1301, EN 27201-2, ISO 7201-2, fire protection, safe handling, transfer procedures, halon recovery.
