On every job site, hazards are above you, beside you, and sometimes hidden in plain sight. Electricians, roofers, construction workers, tree trimmers, and HVAC technicians all face the same threat when working near energized equipment and overhead power lines, and electricity does not give second chances.
Before you start work, take a moment to identify what may be energized. Look for overhead power lines and other energized equipment that may be around you. Check clearances. Always use proper equipment. And never assume lines are de-energized.
A ladder, a length of conduit, a crane boom, or even a tree limb can become energized if you get too close.
