Oklahoma Administrative Code
Title 310 - Oklahoma State Department of Health
Chapter 680 - Residential Care Homes
Subchapter 5 - Construction Requirements and Physical Plant
Section 310:680-5-2 - Plumbing and electrical systems

(a) Electrical, heating, and plumbing facilities must be certified by a licensed plumber, licensed electrician, or municipal building inspector as being in good working order, of safe design and installation, and meet local code requirements.

(b) Water shall be from a public water supply or meet the standards of a public water supply.

(c) Fuel-fire and water heaters must be vented to the outside and have adequate combustion air. They shall not be installed in habitable areas and must be enclosed. Water heaters must have pressure and temperature relief valves. Water heaters and surrounding areas must be kept clean.