Final answer:
Gauge set hoses must have self-sealing connectors or hand valves to prevent environmental damage from refrigerant leaks and to ensure safety during equipment disconnection.
Step-by-step explanation:
Gauge set hoses in fieldwork should have self-sealing connectors or hand valves to prevent refrigerants from leaking into the atmosphere when they are disconnected. This is both an environmental and safety precaution. In HVAC systems, for example, refrigerants can be harmful to the environment, particularly in terms of ozone depletion and global warming potential. The use of self-sealing connectors or hand valves ensures that when the hoses are detached, the valves automatically close, thus minimizing the release of refrigerants. It is a standard practice in the field to prioritize these features to adhere to environmental regulations and to ensure the safety of technicians.