Vet tech jobs
Date:
hook ladder (rigid ladder with a hook at the top to grip a windowsill. This is the type used by firefighters)
Rigid ladders were originally made of wood, but in the 20th century aluminum became more common because it is ligher. Ladders with fiberglass stiles are used for working on electrical wires, because fibreglass is an electrical insulator and provides additional safety for the workers.
For proper use, a rigid ladder should be leaned at a fifteen degree angle. To put it simply, the foot of the ladder should be a quarter of the height of the ladder or less. At steeper angles, the ladder is at risk of falling backwards when the climber leans away too far. At shallower angles, the ladder may lose its grip on the ground. Ladder stabilizers are available that increase the ladder's grip on the ground.