What should electricians look for in work boots?

Read the EH mark on the label, not the toe material. EH describes a sole and heel tested as insulating, in dry conditions, as secondary protection; it never replaces de-energizing the circuit, and a wet or worn sole may not protect. A non-metallic toe is a common pairing but steel-toe boots can carry EH too. Avoid conductive (Cd) footwear around live circuits.