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Breaker Panel Labels

The DO NOT OPERATE WARNING label is for panel boards, circuit breakers and disconnect switches not yet analyzed for hazards. If there is a need to operate a circuit breaker in a panel with either a WARNING label or no label at all, refer to ESG-2010 Premises Power Circuit Breakers and Disconnect Switches: Operating and PPE Requirements. If there is no label, contact the building or area manager.



The NOTICE label is the most common label at SLAC. Most breaker panels are 208/120VAC, fed from transformers rated less than 125kVA and do not have the potential to create an arc flash. To operate breakers enclosed in this panel, the operator must be qualified and wear safety glasses.



The COVERS OR DOORS CLOSED WARNING label is for operating breakers in panels that require more PPE than just safety glasses because there is potential for an arc flash. There is also a Flash Protection Boundary (FPB) distance that must be observed. The level of arc flash is rated by hazard category. A higher category means more energy in an arc flash and a greater potential for injury to a worker. The FPB and the full PPE complement indicated on the label must be observed and worn every time a breaker in the panel is operated.



The DANGER label is a second label that appears on the front of every breaker panel and notifies a qualified worker what PPE is required and what distance must be observed when working on an open panel with exposed busses and breaker connections. The hazards associated with working in a panel with the covers or doors open both are arc flash and electric shock.