DGUV Information 213-013e - SF6-Switchgear and Equipment

Only persons in possession of a certificate of competence pursuant to Regulation (EU) No. 517/2014 may perform work with SF₆.

SF₆ may not be released during work activities on gas compartment (see ChemKlimaschutzV).

When working with SF₆, tasks or practices which generate significant heat build-up, such as welding or smoking, are strictly prohibited in equipment rooms. This restriction must be clearly indicated using prohibitory sign P003 "No naked flames; fire, open ignition sources and smoking prohibited".

Refer to Appendix 1 of the German workplace regulation "Safety and health protection signage" (ASR A1.3).

3.5.1
Initial installation

During a filling procedure, suitable SF₆ maintenance and filling units designed for direct connection to SF₆ gas containers must be used.

During initial installation, new SF₆gas is usually handled.

When using SF₆maintenance units, observe the manufacturers" operating manuals for the SF₆maintenance unit and for the SF₆equipment. After connecting an SF₆maintenance unit to an SF₆gas compartment and/or an SF₆gas container, check the connections for leaks.

The leak-tightness of the gas compartments must be checked according to the manufacturer"s specifications.

3.5.2
Refilling the SF₆gas compartments

During the filling procedure, suitable SF₆ maintenance and filling units designed for direct connection to SF₆ gas containers must be used.

When using SF₆maintenance units, observe the manufacturers" operating manuals for the SF₆maintenance unit and for the SF₆equipment.

After connecting an SF₆maintenance unit to an SF₆gas compartment and/or an SF₆gas container, check the connections for leaks.

3.5.3
Maintenance and upgrade work tasks with gas recovery, including decommissioning and disassembly

SF₆ gas compartments must not be opened before they have been completely emptied (recovery of SF₆ gas) and subsequently flooded with air. The pressure must be equalised to match the atmospheric pressure. It is important here to ensure that a closed SF₆ circuit is restored and that the requirements for initial installation and refilling are met.

When opening or working in or on opened SF₆ gas compartments that have not yet been cleaned and are contaminated with SF₆ decomposition products, the employer must provide the necessary personal protective equipment (PPE) and ensure that it is maintained in proper condition. The employees must use the PPE provided and inspect it every working day (according to Art. 30 of the German accident prevention regulations "Principles of prevention" (DGUV regulation 1) and Art. 7 para. 5 of the German Hazardous Substances Ordinance, GefStoffV).

The following PPE may be required:

• protective gloves,

• protective goggles,

• protective suit,

• shoe covers,

• respiratory protection devices,

• skin protection.

See Appendix 4 for information regarding the selection of personal protective equipment.

Solid decomposition products inside opened SF₆ gas compartments are to be properly removed. An industrial vacuum cleaner designated for dust class H (high) must be used when removing loose dust. This process should be carried out in such a manner that dust is not created or stirred up.

Refer to DIN EN 60335-2-69, Annex AA for information regarding the dust classes associated with industrial vacuum cleaners.

Water-free cleaning fluids and lint-free cleaning cloths should be used when removing firmly caked decomposition products.

When opening or working in or on opened SF₆ gas compartments that have not yet been cleaned, smoking, drinking, eating and storing foodstuffs in the equipment room are strictly prohibited (refer to Art. 8, para. 3 of the German Hazardous Substances Ordinance; GefStoffV). Where necessary, this prohibition must be clearly indicated using prohibitory signs P002 "Smoking prohibited" or P003 "No naked flames; fire, open ignition sources and smoking prohibited" and P022 "Food and beverages prohibited".

Refer to Appendix 1 of the German workplace regulation "Safety and health protection signage" (ASR A1.3).

It is essential to thoroughly wash the facial area, neck, arms and hands prior to taking a break or after completing work. Decomposition dust particles (i.e. switching dust) must be removed from the skin immediately. Dust particles must be removed from the eyes immediately by rinsing thoroughly with plenty of water. A doctor must then be consulted. Solid decomposition products, used cleaning agents and disposable suits as well as used filters from SF₆ switchgear and servicing units, industrial vacuum cleaners or respiratory protection devices must be properly disposed of.

Proper disposal may include collection of the items in dedicated, specially labelled containers for delivery to a specialised waste management company.

Waste code (see AVV):