Final answer:
ASHRAE standards address various systems without a 'safest' classification specific to safety. Chapter 23.8 indicates plastic insulation on live/hot wires prevents both shock and thermal hazards by preventing direct contact and resisting heat.
Step-by-step explanation:
The ASHRAE standards provide guidelines and classifications for various systems, including those related to safety. When considering safety classifications, ASHRAE does not have a 'safest' classification per se, since ASHRAE standards often address different kinds of systems and hazards, which may pertain to energy efficiency, indoor air quality, refrigeration, and other related fields. Within the scope of electrical safety in chapter 23.8, the standards specify the use of electrical safety systems and devices that help to prevent both thermal and shock hazards.
To answer the question about the insulation on live/hot wires, plastic insulation is employed to prevent both shock and thermal hazards. Shock hazards occur when there is a risk of electric current passing through a person's body, while thermal hazards are related to high temperatures that can cause burns or start fires. The insulation effectively prevents direct contact with the live wire and also resists the heat that can be generated by electrical current flowing through the wire, thereby addressing both types of hazards.