Safety, Codes and Standards
Safety, Codes and Standards
This domain tests safe work and code compliance: roof/fall protection, electrical safety, pressure and scald protection, glycol handling, and the standards that govern solar thermal equipment. Expect questions on SRCC OG-100/OG-300, plumbing and mechanical codes, NEC, and permit/inspection requirements.
Job-site safety
Use fall protection at heights required by OSHA (generally 6 ft in construction), secure ladders, and keep roof edges clear. Treat the solar loop as a pressure vessel: isolate and relieve pressure before opening. Hot collectors and glycol can cause burns; wear gloves and eye protection. Do not mix glycol with bleach or other chemicals; dispose of it per local rules.
Codes and standards
Collectors should carry SRCC OG-100 certification; packaged systems may carry OG-300. Plumbing/mechanical codes require pressure relief on storage tanks and solar loops, backflow/cross-connection protection, and a tempering valve where domestic hot water can exceed scald limits. Potable-water heat exchangers should be double-walled. Electrical work must follow the NEC, with GFCI protection where required and disconnects for pumps/controllers.
Worked example
A solar storage tank reaches 170°F, but the home’s hot-water distribution is limited to 120°F by a tempering valve. The valve must be listed for the temperature/pressure and installed with a check valve and accessible strainer per manufacturer. If the valve is missing, the installation fails scald protection even if the collectors and controls work.
Traps
No vacuum breaker or relief valve; single-wall heat exchanger on potable water; missing permit or structural review; unlabeled pipes; no fall protection; and using non-listed components. Keep manufacturer instructions and SRCC listings on site for the inspector.