Health, safety and environmental compliance in refrigeration and air conditioning work
Duty holders and the hierarchy of control
Every job begins with the employer's duties under the Health and Safety at Work etc. Act, plus the duties owed to non-employees and to other contractors on site. A risk assessment is only usable when it is site-specific and feeds directly into the method statement and, where required, the permit to work. Controls must follow the hierarchy: eliminate, substitute, engineer, administrate, then PPE as the last line. Questions often present a scenario where PPE is chosen first - that is the wrong answer.
Refrigerant hazards and safety groups
Always state the safety group and the charge together. A1: R410A, R134a, R744. A2L: R32, R1234yf. A3: R290 (propane). B2L: R717 (ammonia). Traps include assuming R410A is flammable (it is not), assuming CO2 is inherently safe (it is asphyxiant and runs at very high pressure), and confusing A2L with A3 - A2L needs ignition-source control, charge limits and ventilation, not the full A3 regime.
Process and physical hazards
Asphyxiation risk in basements and plant rooms, especially with CO2 and ammonia; hot work and brazing fire risk under a permit; pressure testing under PSSR 2000 using regulators and calibrated gauges; never use oxygen as a purge gas - use oxygen-free nitrogen only. COSHH covers oils, acids, cleaners and leak-detection dyes; LOLER covers lifting; manual handling and work at height are routine.
Environmental compliance
Refrigerant must never be vented. Recovered gas is consigned as hazardous waste with correct documentation; waste oil, contaminated filters and desiccants are segregated. Spill kits and emergency procedures belong in the method statement.
Rule of thumb
If the total charge in an occupied space could exceed the practical limit for that safety group, you need mitigation - leak detection, ventilation, an alarm or a machinery-room location - before you need a bigger toolbox.