SECTION 310:661-8-11. Temperature and ventilating systems

(a)   An indoor design temperature of 75°F. (24°C.) (winter design conditions) shall be provided for all occupied areas.

(b)   All air supply and air-exhaust systems shall be mechanically operated. All fans serving exhaust systems shall be located at the discharge end of the system. The ventilating systems shall comply with the requirements of the appropriate edition of the International Mechanical Code.

(c)   Outdoor air intakes shall be located not less than ten feet (10' 0") from exhaust outlets of ventilating systems, combustion equipment stacks, plumbing vent stacks, or from areas which may collect vehicular exhaust and other noxious fumes. The bottom of outdoor air intakes serving central systems shall be located as high as practical but not less than three feet (3' 0") above ground level, or if installed above the roof, one foot (1' 0") above roof level.

(d)   Corridors shall not be used to supply air to or exhaust air from any room, except that air from corridors may be used to ventilate bathrooms, toilet rooms, and janitors' closets.

(e)   All central ventilating or air conditioning systems shall be equipped with filters. The filter bed shall be located upstream of the air conditioning equipment, unless a prefilter is employed. In this case, the prefilter shall be upstream of the equipment and the main filter bed may be located further downstream.

(f)   All filter efficiencies shall be average atmospheric dust spot efficiencies tested in accordance with ASHRAE Standard 52-68. A manometer shall be installed across each filter bed serving central air systems. The filter efficiencies for central ventilation and air conditioning system should follow the table shown on Appendix A.

(g)   Exhaust hoods in food preparation centers shall be in compliance with NFPA 96 and the International Mechanical Code (IMC).

(h)   Boiler rooms shall be provided with sufficient outdoor air to maintain combustion rates of equipment and to limit temperatures in working stations to 97°F. (36°C.), Effective Temperatures (ET) as defined by ASHRAE "Handbook of Fundamentals", without creating negative air pressure in any room housing fire equipment.

(i)   Where individual mechanical exhaust systems are used to exhaust patient toilets or bathrooms, the individual ventilation fan shall run continuously. All mechanical ventilating equipment including under window and exhaust systems shall operate continuously.

(j)   Wall or baseboard electrical heaters shall not be used.

(k)   Detectors in central ventilating systems shall be in accordance with NFPA 90A.

(l)   All ducts shall be in concealed spaces.

(m)   All smoke dampers on any one air conditioning system shall be controlled by unit mounted return air and supply air smoke detectors, which will act to close all of the smoke dampers on that system and stop the fan. Smoke dampers shall also close and the fan shall stop when the fire alarm system is activated and/or the sprinkler system is energized.

(n)   All isolation rooms shall have all air directly exhausted to the exterior without recirculation. There shall be a negative pressure relationship between the patient room and adjacent areas. The differential pressure shall be a minimum of 0.01" water gage (2.5 Pa). If alarms are installed, allowances shall be made to prevent nuisance alarms of monitoring devices.

(o)   Ventilation for all isolation rooms shall provide for a minimum twelve (12) air changes per hour including two (2) air changes per hour of outside air. Patient sleeping rooms shall provide a minimum of two (2) air changes per hour with at least two (2) of these air changes being outside air. Soiled holding and workroom areas shall have a minimum of ten (10) air changes per hour. All other rooms shall comply with the ventilation requirements of the International Mechanical Code as adopted by the State of Oklahoma.

[Source: Added at 21 Ok Reg 1303, eff 5-27-04]