Final answer:
Class G hard hats are specified for electrical work, safeguarding against 20,000 volts to protect workers in high-voltage environments.
Step-by-step explanation:
The Class G hard hats are designed for electrical work and are rated for protection against 20,000 volts. These hard hats are necessary to ensure the safety of workers who may come into contact with high-voltage environments. It's important for individuals working in such conditions to use the appropriate personal protective equipment to prevent electrical shocks and other related injuries.