ASHRAE+62.1-2022+(1) - Page 011
Extracted Content
b. the separation walls include an air barrier consisting of a continuous membrane or surface treat ment in the separation wall that has documented resistance to air leakage—continuity of the barrier shall be maintained at openings for pipes, ducts, and other conduits and at points where the barrier meets the outside walls and other barriers; and c. interior corridors common to ETS and ETS-free areas are mechanically supplied with outdoor air
at the rate of 0.1 cfm/ft [2] (0.5 L/s·m [2] ). 2. Adjacent spaces otherwise required to be held at negative pressure and posted with signs due to the presence of hazardous or flammable materials or vapors.
Informative Note: Examples of methods for demonstrating relative pressure include engineering analysis, pressure differential measurement, and airflow measurement.
5.3.3 Separation. Solid walls, floors, ceilings, and doors equipped with automatic closing mechanisms shall separate ETS areas from ETS-free areas.
Exception to 5.3.3: Openings without doors are permitted in the separation where engineered systems are
designed to provide airflow from ETS-free areas into ETS areas, notwithstanding eddies that may occur in the immediate vicinity of the boundary between the ETS and ETS-free areas and reverse flow that may occur due to short-term conditions such as wind gusts.
Informative Note: Examples of methods for demonstrating air motion are engineering analysis and the use of a directional airflow indicator at representative locations in the opening, such as on 1 ft (0.3 m) centers or at locations required for duct traverses in standard testing and balancing procedures, such as those described in ASHRAE Standard 111.
5.3.4 Transfer Air. When air is transferred from ETS-free areas to ETS areas, the transfer airflow rate shall be maintained regardless of whether operable doors or windows between ETS-free and ETS areas are opened or closed. Acceptable means of doing so include fixed openings in doors, walls, or floors, transfer grilles, transfer ducts, or unducted air plenums with air pressure differentials in compliance with Section 5.3.2.
5.3.5 Recirculation. Air-handling and natural ventilation systems shall not recirculate or transfer air from an ETS area to an ETS-free area.
5.3.6 Exhaust Systems. Exhaust or relief air from an ETS area shall be discharged such that none of the air is recirculated back into any ETS-free area.
5.3.7 Signage. A sign shall be posted outside each entrance to each ETS area. The sign shall state, as a minimum, “This Area May Contain Environmental Tobacco Smoke,” in letters at least 1 in. (25 mm) high or otherwise in compliance with accessibility guidelines.
Exception to 5.3.7: Instead of the specified sign, equivalent notification means acceptable to the AHJ
may be used.
Informative Note: Based on the definition of “ETS area,” such a sign might be posted outside a larger ETS area that includes the area where smoking is permitted.
5.3.8 Reclassification. An area that was previously an ETS area but now meets the requirements of an ETS-free area shall be permitted to be classified as such where smoke exposure has stopped and odor and irritation from residual ETS contaminants are not apparent.
5.4 Outdoor Air Intakes. Ventilation system outdoor air intakes shall be designed in accordance with the following subsections.
5.4.1 Location. Outdoor air intakes (including openings that are required as part of a natural ventilation system) shall be located such that the shortest distance from the intake to any specific potential outdoor contaminant source listed in Table 5-1 shall be equal to or greater than
a. the separation distance in Table 5-1 or b. the calculation methods in Normative Appendix B
and shall comply with all other requirements of this section.
5.4.1.1 Exhaust/Relief Outlets. Separation criteria for Class 2 and Class 3 exhaust/relief outlets apply to the distance from the outdoor air intakes for one ventilation system to the exhaust outlets and relief outlets for any other ventilation system.
5.4.1.2 Fuel-Burning Equipment. The minimum distances relative to fuel-fired appliances shall be as required by ANSI Z223.1/NFPA 54 for fuel-gas-burning appliances and equipment, NFPA 31 for oil-burning appliances and equipment, and NFPA 211 for other combustion appliances and equipment.
ANSI/ASHRAE Standard 62.1-2022 9