Circuit breakers within a building's electricity distribution system can be tripped by someone drilling through a power cable, or by switching the wrong circuit off to perform maintenance.
(Circuit breakers within a building's electricity distribution system; can be tripped; by someone drilling) (Circuit breakers within a building's electricity distribution system; by switching off; to perform maintenance)
Circuit breakers within a building's electricity distribution system Circuit breakers within a building's electricity distribution system
can be tripped by switching off
by someone drilling
to perform maintenance