Practical handling
Basic rule with flammable gas:
Do what you can to avoid working or operating equipment in a flammable atmosphere.
If you can not avoid to, eliminate ignition sources.
In most investigations, the risks during commissioning, maintenance and repair are considered higher than during construction or normal operation of the refrigeration system.
For work with flammable refrigerant, the generally necessary work risk assessment shall be extended by the additional risks caused by the flammability. In ISO12100 these are classified as thermal risks. Sound engineering practice, work according to safety codes and standards, and a skilled worker are precondition for safe work, especially with flammable refrigerant. This includes a risk assessment for the maintenance or repair work to be performed on site.
Parts of this could be in the system documentation, parts are done on site by a skilled technician or engineer, together with the system operator. Here some example cases are shown from this field, that do not list all necessary routine steps well know by skilled workers, but highlight the special focus because of A2L flammability.
A flammable refrigerant air mixture can basically appear in two places:
- Inside the refrigeration system
- During maintenance and repair this can be avoided by proper work procedures. Refrigerant shall only enter a component, if the repaired part is tested for tightness and the air is evacuated out.
- Around the refrigeration system
- This can, to a large extend, be avoided by proper work procedures. If it can not be avoided, ignition sources for A2L air mixture have to be avoided.