The nursing home must ensure:

(1) Ventilation of all rooms is designed to prevent objectionable odors, condensation, and direct drafts on the residents;

(2) All habitable space is mechanically ventilated including:

(a) Air supply and air exhaust systems;

(b) Installation of air-handling duct systems according to the requirements of the International Mechanical Code and chapter 51-52 WAC;

(d) Installation of exhaust grilles on or near the ceiling; and

(e) Outdoor air intakes located a minimum of twenty-five feet from the exhaust from any ventilating system, combustion equipment, or areas which may collect vehicular exhaust and other noxious fumes, and a minimum of ten feet from plumbing vents. The nursing home must locate the bottom of outdoor air intakes serving central systems a minimum of three feet above adjoining grade level or, if installed through the roof, three feet above the highest adjoining roof level.

(3) Minimum ventilation requirements meet the pressure relationship and ventilation rates per ASHRAE 2007 HVAC Applications Chapter 7.11 Table 6, Pressure Relationships and Ventilation of Certain Areas of Nursing Homes.

TABLE 6

PRESSURE RELATIONSHIPS AND VENTILATION OF CERTAIN AREAS OF NURSING HOMES

Function Area	Pressure Relationship To Adjacent Areas1,2	Minimum Air Changes of Outdoor Air Per Hour Supplied To Room	Minimum Total Air Changes Per Hour Supplied To Room	All Air Exhausted Directly To Outdoors	Air Recirculated Within Room Units
RESIDENT CARE
Resident room (holding room)	±	2	4	Optional	Optional
Resident corridor	±	Optional	2	Optional	Optional
Toilet room	N	Optional	10	Yes	No
Resident gathering (dining, activity)	±	2	4	Optional	Optional
DIAGNOSTIC AND TREATMENT
Examination room	±	2	6	Optional	Optional
Physical therapy3	N	2	6	Optional	Optional
Occupational therapy3	N	2	6	Optional	Optional
Soiled workroom or soiled holding	N	2	10	Yes	No
Clean workroom or clean holding	P	2	4	Optional	Optional
STERILIZING AND SUPPLY
Sterilizer exhaust room	N	Optional	10	Yes	No
Linen and trash chute room	N	Optional	10	Yes	No
Laundry, general3	±	2	10	Yes	No
Soiled linen sorting and storage	N	Optional	10	Yes	No
Clean linen storage	P	Optional	2	Yes	No
SERVICE
Food preparation center3	±	2	10	Yes	Yes
Warewashing room3	N	Optional	10	Yes	Yes
Dietary day storage	±	Optional	2	Yes	No
Janitor closet	N	Optional	10	Yes	No
Bathroom	N	Optional	10	Yes	No
Personal services (barber/salon)	N	2	10	Yes	No

1/	P=Positive N=Negative ±=Continuous directional control not required.
2/	Whether positive or negative, pressure must be a minimum of seventy cubic feet per minute (CFM).
3/	The volume of air may be reduced up to fifty percent in these areas during periods of nonuse. The soiled holding area of the general laundry must maintain its full ventilation capacity at all times.

(4) Individual exhaust systems meet the following requirements:

(a) Where individual mechanical exhaust systems are used to exhaust individual toilet rooms or bathrooms, the individual ventilation fans are interconnected with room lighting to ensure ventilation while room is occupied. The ventilation fan must have a time delay shutoff to ensure that the exhaust continues for a minimum of five minutes after the light switch is turned off; and

(b) The volume of air removed from the space by exhaust ventilation is replaced directly or indirectly by an equal amount of tempered/conditioned air.

(5) Central exhaust systems meet the following requirements:

(a) All fans serving central exhaust systems are located to prevent a positive pressure in the duct passing through an occupied area; and

(b) Fire and smoke dampers are located and installed in accordance with the International Building Code, Standards and amendments in chapter 51-50 WAC.

(6) Air filters meet the following requirements:

(a) All central ventilation or air-conditioning systems are equipped with filters per ASHRAE 2007 HVAC Applications Chapter 7.11 Table 5, Filter Efficiencies for Central Ventilation and Air Conditioning Systems in Nursing Homes and meet the following requirements:

Table 5
Filter Efficiencies for Central Ventilation and Air-Conditioning Systems in Nursing Homes
FUNCTION AREA	Minimum Number of Filter Beds	Filter Efficiency of Main Filter Bed, MERV*
Resident care, treatment, diagnostic, and related areas	1	15
Food preparation areas and laundries	1	8
Administrative, bulk storage, and soiled holding areas	1	6
*MERV = Minimum Efficiency Reporting Value

(b) Central ventilation or air conditioning systems means any system serving more than a single room used by residents or by any group of rooms serving the same utility function (i.e., the laundry);

(c) Filter efficiency is warranted by the manufacturer and is based on atmospheric dust spot efficiency per ASHRAE Standard 52.2;

(d) The filter bed is located upstream of the air-conditioning equipment, unless a prefilter is employed. In which case, the prefilter is upstream of the equipment and the main filter bed may be located downstream;

(e) Filter frames are durable and provide an airtight fit with the enclosing duct work. All joints between filter segments and enclosing duct work are gasketed or sealed;

(f) All central air systems have a manometer installed across each filter bed with an alarm to signal high pressure differential; and

(g) Humidifiers, if provided, are a steam type.

PDFWAC 388-97-4040

Ventilation systems in new construction.