Outside Air Requirements

Outside Air Requirements: Must Be Met in All Commercial Projects and some Residential Projects. Generally, Outside Air Recommendation is .5 cfm of Pool and Deck Area or 15cfm per person, whichever is greater.

PER AHSRAE STANDARD 62-1989

“Ventilation for Acceptable Indoor Air Quality”

Par. 5.1 “When infiltration and natural ventilation are insufficient to meet ventilation air requirements, mechanical ventilation shall be provided”.

Par. 5.6 “Ventilating ducts and plenums shall be constructed and maintained to minimize the opportunity for growth and dissemination of micro-organisms through the ventilation system”. We recommend minimum 50%, maximum 60% RH (relative humidity) within the space.

CALCULATION PROCEDURE

  1. From ASHRAE 62-1989, Table 2:Outdoor Air Requirements for swimming pools is 0.50 CFM/sq.ft. of pool and deck area.
  2. Same Table indicates outdoor air requirements for spectator facilities is 15 CFM/person.
  3. Par. 6.1.3.4 indicates that outdoor air requirements for intermittent used spaces may be reduced by 50%.
SUMMARY TABLE
POOL & DECK AREA (SQ. FT.) MINIMUM BUILDING OUTSIDE AIR (CFM) Per 6.1.3.4 MINIMUM BUILDING OUTSIDE AIR (CFM) (WITHOUT 6.1.3.4) MINIMUM NUMBER OF OCCUPANTS (Per 6.1.3.4)
1,000 250 500 33
2,000 500 1,000 66
5,000 1,250 2,500 166
10,000 2,500 5,000 333
15,000 3,750 7,500 500
20,000 5,000 10,000 666
25,000 6,250 12,500 833
30,000 7,500 15,000 1,000

Note: Add 7.5 CFM for each additional occupant if using par 6.1.3.4

Note: Add 15 CFM for each additional occupant if not using par 6.1.3.4

Note: Outside Air Requirements must be met in all commercial indoor pool projects; not necessarily required in residential. Follow your own state/local/mechanical codes. Generally outside air requirements are for commercial projects. Determine if your area is following BOCA National or BOCA International Codes. Review all standards for current applicable data.

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