420.0 Air Distribution Devices. [OSHPD 1, 2, 3, 4 & 5]

All air distribution devices and supply air outlets shall meet the requirements of ASHRAE 170-2013, Section 6.7.2 and Table 6.7.2.

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TABLE 4-A PRESSURE RELATIONSHIP AND VENTILATION REQUIREMENTS FOR GENERAL ACUTE CARE HOSPITALS, SKILLED NURSING FACILITIES, INTERMEDIATE CARE FACILITIES, CORRECTIONAL

TREATMENT CENTERS, OUTPATIENT FACILITIES, AND LICENSED CLINICS

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TABLE 4-A (continued) PRESSURE RELATIONSHIP AND VENTILATION REQUIREMENTS FOR GENERAL ACUTE CARE HOSPITALS, SKILLED NURSING FACILITIES, INTERMEDIATE CARE FACILITIES, CORRECTIONAL

TREATMENT CENTERS, OUTPATIENT FACILITIES, AND LICENSED CLINICS

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TABLE 4-A (continued) PRESSURE RELATIONSHIP AND VENTILATION REQUIREMENTS FOR GENERAL ACUTE CARE HOSPITALS, SKILLED NURSING FACILITIES, INTERMEDIATE CARE FACILITIES, CORRECTIONAL

TREATMENT CENTERS, OUTPATIENT FACILITIES, AND LICENSED CLINICS

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TABLE 4-A (continued) PRESSURE RELATIONSHIP AND VENTILATION REQUIREMENTS FOR GENERAL ACUTE CARE HOSPITALS, SKILLED NURSING FACILITIES, INTERMEDIATE CARE FACILITIES, CORRECTIONAL

TREATMENT CENTERS, OUTPATIENT FACILITIES, AND LICENSED CLINICS

Note: NR = No requirement Notes for Table 4-A: a. Except where indicated by a “No” in this column, recirculating room HVAC units (with heating or cooling coils) are acceptable for providing that portion

of the minimum total air changes per hour that is permitted by Section 407.4.1.7 . Because of the cleaning difficulty and potential for buildup of contamination, recirculating room units shall not be used in areas marked “No.” Recirculating devices with HEPA filters shall be permitted in existing facilities as interim, supplemental environmental controls to meet requirements for the control of airborne infectious agents. The design of either portable or fixed systems should prevent stagnation and short circuiting of airflow. The design of such systems shall also allow for easy access for scheduled preventative maintenance and cleaning. b. Additional air change, ISO class, continuous pressure monitoring and filtering requirements for compounding areas shall comply with California Board of

rne infectious agents. The design of either portable or fixed systems should prevent stagnation and short circuiting of airflow. The design of such systems shall also allow for easy access for scheduled preventative maintenance and cleaning. b. Additional air change, ISO class, continuous pressure monitoring and filtering requirements for compounding areas shall comply with California Board of

Pharmacy regulations Title 16 §1735 & §1751, and USP <797> & <800>. Air supplied to the compounding buffer room and ante room must be introduced through 99.97% minimum HEPA filters located in the ceiling. At least 15 air changes per hour (ACPH) shall be provided to nonhazardous drug (non-HD) compounding buffer rooms through the ceiling. The HEPA filtered air from the PEC in the non-HD buffer room, when added to the HVAC-supplied HEPA- filtered air, shall increase the total HEPA-filtered ACPH to at least 30. If the PEC is used to meet the minimum total ACPH requirements, the PEC must not be turned off except for maintenance. All hazardous drug (HD) compounding areas and PECs shall be exhausted externally through 99.97% HEPA filtration. For both hazardous and non-hazardous compounding, minimum air changes shall be met under dynamic operating conditions as defined by USP. Returns and exhaust grilles shall be mounted low on the wall unless a visual smoke study demonstrates dilution of particles and sweeping out of particles from the entire room. One return/exhaust should be placed near the refrigerator compressor. Anteroom shall have a minimum pressure differential of +0.02 inches water column in relation to the adjacent, non-compounding spaces. Non-HD buffer room shall have a pressure differential of +0.02 to +0.05 inches water column in relation to the anteroom. HD buffer room shall have a pressure differential of -0.01 to -0.03 inches water column in relation to the anteroom. c. The term trauma room as used herein is a first-aid room and/or emergency room used for general initial treatment of accident victims. The operating room

within the trauma center that is routinely used for emergency surgery is considered to be an operating room by this standard. d. Pressure relationships need not be maintained when the room is unoccupied. e. See Section 7.2 of ASHRAE 170 and its subsections for pressure-relationship requirements. f. For operating rooms, cardiac catheterization labs, angiography rooms, cystoscopy rooms, delivery rooms, cesarean operating rooms, newborn intensive care,

rgency surgery is considered to be an operating room by this standard. d. Pressure relationships need not be maintained when the room is unoccupied. e. See Section 7.2 of ASHRAE 170 and its subsections for pressure-relationship requirements. f. For operating rooms, cardiac catheterization labs, angiography rooms, cystoscopy rooms, delivery rooms, cesarean operating rooms, newborn intensive care,

and nurseries provide approximately 15% excess supply air to the room or a sufficient quantity of excess supply air to maintain an appropriate positive air balance based on the room tightness and number of doors. For all rooms not listed in this footnote or not listed in Section 322.0 requiring either a positive or negative air balance, provide approximately 10% differential cfm between supply and return/exhaust airflow but not less than 25 cfm differential shall be provided regardless of room size. Room function, size, and tightness may be considered when determining the differential airflow required. Where continuous directional control is not required, variations between supply cfm and return or exhaust cfm shall be minimized in accordance with Section 407.4.1.3. g. All air need not be exhausted if darkroom equipment has a scavenging exhaust duct attached and meets ventilation standards regarding NIOSH, OSHA, and

local employee exposure limits. ^{2, 3}

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h. A nonrefrigerated body-holding room is applicable only to facilities that do not perform autopsies on-site and use the space for short periods while waiting

for the body to be transferred. i. Minimum total air changes per hour (ach) shall be that required to provide proper makeup air to kitchen exhaust systems as specified in ANSI/ASHRAE Standard 154. ⁴ In some cases, excess exfiltration or infiltration to or from exit corridors compromises the exit corridor restrictions of NFPA 90A, ⁵ the pressure requirements of NFPA 96, ⁶ or the maximum defined in the table. During operation, a reduction to the number of air changes to any extent required for odor control shall be permitted when the space is not in use. (See FGI [2010] in Informative Appendix B.) j. In some areas with potential contamination and/or odor problems, exhaust air shall be discharged directly to the outdoors and not recirculated to other areas. Individual circumstances may require special consideration for air exhausted to the outdoors. To satisfy exhaust needs, constant replacement air from the outdoors is necessary when the system is in operation. k. The RH ranges listed are the minimum and/or maximum allowable at any point within the design temperature range required for that space. l. Systems shall be capable of maintaining the rooms within the range during normal operation. Lower or higher temperature shall be permitted when patients’ comfort and/or medical conditions require those conditions. m. National Institute for Occupational Safety and Health (NIOSH) criteria documents regarding occupational exposure to waste anesthetic gases and vapors, and

required for that space. l. Systems shall be capable of maintaining the rooms within the range during normal operation. Lower or higher temperature shall be permitted when patients’ comfort and/or medical conditions require those conditions. m. National Institute for Occupational Safety and Health (NIOSH) criteria documents regarding occupational exposure to waste anesthetic gases and vapors, and

control of occupational exposure to nitrous oxide ⁷ indicate a need for both local exhaust (scavenging) systems and general ventilation of the areas in which the respective gases are utilized. Refer to NFPA 99 for other requirements. ⁸ n. If pressure-monitoring device alarms are installed, allowances shall be made to prevent nuisance alarms. Short-term excursions from required pressure rela tionships shall be allowed while doors are moving or temporarily open. Simple visual methods such as smoke trail, ball-in-tube, or flutterstrip shall be permitted for verification of airflow direction. o. Surgeons or surgical procedures may require room temperatures, ventilation rates, humidity ranges, and/or air distribution methods that exceed the minimum

indicated ranges. p. Treatment rooms used for bronchoscopy shall be treated as bronchoscopy rooms. Treatment rooms used for procedures with nitrous oxide shall contain pro visions for exhausting anesthetic waste gases. q. In a recirculating ventilation system, HEPA filters shall be permitted instead of exhausting the air from these spaces to the outdoors provided that the return

air passes through the HEPA filters before it is introduced into any other spaces. The entire minimum total air changes per hour of recirculating airflow shall pass through HEPA filters. When these areas are open to larger, nonwaiting spaces, the exhaust air volume shall be calculated based on the seating area of the waiting area. ( Note: The intent here is to not require the volume calculation to include a very large space [e.g., an atrium] just because a waiting area opens onto it.) r. See NFPA 99 for further requirements. ⁸ s. For intermediate care, labor/delivery/recovery rooms, and labor/delivery/recovery/postpartum rooms, four total ach shall be permitted when supplemental

ting area of the waiting area. ( Note: The intent here is to not require the volume calculation to include a very large space [e.g., an atrium] just because a waiting area opens onto it.) r. See NFPA 99 for further requirements. ⁸ s. For intermediate care, labor/delivery/recovery rooms, and labor/delivery/recovery/postpartum rooms, four total ach shall be permitted when supplemental

heating and/or cooling systems (radiant heating and cooling, baseboard heating, etc.) are used. t. The protective environment airflow design specifications protect the patient from common environmental airborne infectious microbes (i.e., Aspergillus spores). The anteroom shall have negative air pressure in relation to the protective environment room. A door louver, transfer grille, or other acceptable means may be provided to allow for airflow from the protective environment room to the anteroom. The protective environment room shall have positive- pressure in relation to the anteroom and adjoining toilet room. Recirculation HEPA filters shall be permitted to increase the equivalent room air exchanges; however, the outdoor air changes are still required. Constant-volume airflow is required for consistent ventilation for the protected environment. The pressure relationship to adjacent areas shall remain unchanged if the PE room is utilized as a normal patient room. Rooms with reversible airflow provisions for the purpose of switching between protective environment and AII functions shall not be permitted. u. The AII room described in this standard shall be used for isolating the airborne spread of infectious diseases, such as measles, varicella, or tuberculosis. The

djacent areas shall remain unchanged if the PE room is utilized as a normal patient room. Rooms with reversible airflow provisions for the purpose of switching between protective environment and AII functions shall not be permitted. u. The AII room described in this standard shall be used for isolating the airborne spread of infectious diseases, such as measles, varicella, or tuberculosis. The

airborne infection isolation room shall have negative pressure in relation to the anteroom, and the adjoining toilet room shall have negative pressure in rela- tion to the airborne infection isolation room. Supplemental recirculating devices using HEPA filters shall be permitted in the AII room to increase the equivalent room air exchanges; however, the minimum outdoor air changes of Table 4-A are still required. AII rooms that are retrofitted from standard patient rooms from which it is impractical to exhaust directly outdoors may be recirculated with air from the AII room, provided that air first passes through a HEPA filter. When the AII room is not utilized for airborne infection isolation, the pressure relationship to adjacent areas, when measured with the door closed, shall remain unchanged and the minimum total air change rate shall be 6 ach. Switching controls for reversible airflow provisions shall not be permitted. The anteroom shall have positive air pressure in relation to the airborne infection isolation room. A door louver, transfer grille, or other acceptable means may be provided to allow for airflow from the anteroom to the airborne infection isolation room. v. When required, appropriate hoods and exhaust devices for the removal of noxious gases or chemical vapors shall be provided in accordance with NFPA 99. ⁸ w. The requirement that all room air is exhausted directly to outdoors applies only to radiology waiting rooms programmed to hold patients who are waiting for

chest x-rays for diagnosis of respiratory disease. x. If the planned space is designated in the organization’s operational plan to be utilized for both bronchoscopy and gastrointestinal endoscopy, the design param eters for “bronchoscopy, sputum collection, and pentamidine administration” shall be used. y. For single-bed patient rooms using Group D diffusers, a minimum of six total ach shall be provided and calculated based on the volume from finished floor

to 6 ft (1.83 m) above the floor. z. This table is based on Table 7.1 in ASHRAE 170, “Ventilation of Healthcare Facilities”, and is used with expressed written permission from ASHRAE. aa.Nurse station pressure relationship and ventilation requirements shall match the area in which it is located. ab.HD segregated compounding area shall have a differential pressure of -0.01 to -0.03 inches water column in relation to adjacent areas and a minimum of

12 air changes per hour.

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TABLE 4-B FILTER EFFICIENCIES FOR CENTRAL VENTILATION AND AIR-CONDITIONING SYSTEMS IN GENERAL ACUTE

CARE HOSPITALS, ACUTE PSYCHIATRIC HOSPITALS, OUTPATIENT FACILITIES, AND LICENSED CLINICS ¹

1 Based on ASHRAE 52.2. 2 Based on DOP test in accordance with MIL-STD-282 or based on ASHRAE 52.2. 3 HEPA filters at air outlet or other locations when approved by the Authority Having Jurisdiction. 4 HEPA filter located in the supply duct which serves the positive-pressure isolation room or rooms may serve more than one supply outlet and more than one positive-pressure isolation room. HEPA filter or a filter with minimum efficiency reporting value (MERV) of 17 installation shall be designed and equipped to permit safe removal, disposal and replacement of filters. 5 The numbers in parentheses represent MERV rating based on ASHRAE 52.2.

TABLE 4-C FILTER EFFICIENCIES FOR CENTRAL VENTILATION AND AIR-CONDITIONING SYSTEMS IN SKILLED NURSING FACILITIES AND INTERMEDIATE CARE FACILITIES AND CORRECTIONAL TREATMENT CENTERS ¹

2 Filters are not required for evaporative coolers serving laundries and food preparation areas. 3 The numbers in parentheses represent MERV rating based on ASHRAE 52.2.

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TABLE 402.1 MINIMUM VENTILATION RATES IN BREATHING ZONE ^{1, 2}

[ASHRAE 62.1: TABLE 6.2.2.1] Note: Ventilation air supply requirements for occupancies regulated by the California Energy Commission are found in the California Energy Code.

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TABLE 402.1 (continued) MINIMUM VENTILATION RATES IN BREATHING ZONE ^{1, 2}

[ASHRAE 62.1: TABLE 6.2.2.1]

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For SI units: 1 cubic foot per minute = 0.0283 m ³ /min, 1 square foot = 0.0929 m ² Notes: 1 This table applies to no-smoking areas. Rates for smoking-permitted spaces shall be determined using other methods. 2 Volumetric airflow rates are based on dry air density of 0.075 pounds of dry air per cubic foot (lbda/ft3) (1.201 kgda/m3) at a barometric pressure of 1 atm (101 kPa) and an air temperature of 70°F (21°C). Rates shall be permitted to be adjusted for actual density. 3 The default occupant density shall be used where actual occupant density is not known. 4 Where the occupancy category for a proposed space or zone is not listed, the requirements for the listed occupancy category that is most similar in terms of occupant density, activities, and building construction shall be used.

ature of 70°F (21°C). Rates shall be permitted to be adjusted for actual density. 3 The default occupant density shall be used where actual occupant density is not known. 4 Where the occupancy category for a proposed space or zone is not listed, the requirements for the listed occupancy category that is most similar in terms of occupant density, activities, and building construction shall be used.

ITEM-SPECIFIC NOTES FOR TABLE 402.1 a For high school and college libraries, the values shown for “Public Assembly Spaces – Libraries” shall be used. b Rate may not be sufficient where stored materials include those having potentially harmful emissions. c Rate does not allow for humidity control. “Deck area” refers to the area surrounding the pool that is capable of being wetted during pool use or when the

pool is occupied. Deck area that is not expected to be wetted shall be designated as an occupancy category. d Rate does not include special exhaust for stage effects such as dry ice vapors and smoke. e Where combustion equipment is intended to be used on the playing surface or in the space, additional dilution ventilation, source control, or both shall be pro vided. f Default occupancy for dwelling units shall be two persons for studio and one-bedroom units, with one additional person for each additional bedroom. g Air from one residential dwelling shall not be recirculated or transferred to other spaces outside of that dwelling. h Ventilation air for this occupancy category shall be permitted to be reduced to zero where the space is in occupied-standby mode.

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TABLE 403.2.2 ZONE AIR DISTRIBUTION EFFECTIVENESS1, 2, 3, 4, 5 [ASHRAE 62.1: TABLE 6.2.2.2]

1 “Cool air” is air cooler than space temperature. 2 “Warm air” is air warmer than space temperature. 3 “Ceiling supply” includes any point above the breathing zone. 4 “Floor supply” includes any point below the breathing zone. 5 As an alternative to using the above values, Ez shall be permitted to be regarded as equal to air change effectiveness determined in accordance with ASHRAE 129 for air distribution configurations except unidirectional flow. 6 For lower velocity supply air, Ez = 0.8

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TABLE 403.7 MINIMUM EXHAUST RATES

[ASHRAE 62.1: TABLE 6.5]

For SI units: 1 cubic foot per minute = 0.0283 m ³ ⁄ min, 1 square foot = 0.0929 m ² Notes: 1 Stands where engines are run shall have exhaust systems that directly connect to the engine exhaust and prevent escape of fumes. 2 Where combustion equipment is intended to be used on the playing surface, additional dilution ventilation, source control, or both shall be provided. 3 Exhaust shall not be required where two or more sides comprise walls that are at least 50 percent open to the outside. 4 Rate is per water closet, urinal, or both. Provide the higher rate where periods of heavy use are expected to occur. The lower rate shall be permitted to be used otherwise. 5 Rate is for a toilet room intended to be occupied by one person at a time. For continuous system operation during normal hours of use, the lower rate shall be permitted to be used. Otherwise the higher rate shall be used. 6 For refrigeration machinery rooms, the exhaust rate shall comply with Chapter 11. 7 For continuous system operation, the lower rates shall be permitted. Otherwise the higher rate shall be used. 8 For unlisted occupancies for a proposed space not listed in the table, the requirements for the listed occupancy that is most similar in terms of occupant density and occupancy type shall be used. 9 Exhaust air that has been cleaned in accordance with the criteria of Class 1 shall be permitted to be recirculated. 10 Rate is per shower head. 11 [HCD 1 & HCD 2] A bathroom is any room containing a bathtub, a shower, a spa, or a similar source of moisture. 12 [HCD 1 & HCD 2] ANSI/ASHRAE 62.2: Tables 5.1 and 5.2.

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CALIFORNIA MECHANICAL CODE – MATRIX ADOPTION TABLE