|
Selection of all materials of construction for a pool area is extremely important based upon the corrosive atmosphere created by the pool's humidity and the chemicals used in maintenance. The air conditioning system requires the same jurisprudence. Pool areas must have their own HVAC system. Because of the nature of human activity, excessive drafts and air motion must be avoided. If possible, the pool area should be isolated from the rest of the facility. The pool area should be under a negative pressure9 (0.05 to 0.15 inches of water) with respect to the rest of the facility.
Pool HVAC systems often include a reheat system to dehumidify during periods when outdoor humidity may be high. When outside conditions are appropriate these units may use up to 100% outside air to condition/dehumidify the pool area. This taxes the HVAC system in the effort to maintain design conditions10 for educational facility pool areas at 75° to 85° F. Care should be exercised to maintain the relative humidity between 50% and 60% due to the evaporative cooling effect on a person emerging from the pool. A higher humidity level will encourage corrosion and condensation.
The type of air distribution system influences the amount of air introduced into the pool area. Air volume above the minimum calculated value to maintain comfort may be recirculated provided the recirculated air is dehumidified and filtered to reduce contaminants to safe levels. Filters should be chosen based upon construction to avoid reaction with air contaminants. The minimum dust spot efficiency, per ASHRAE 52.1-1992, should be 45% to 60% to minimize streaking of walls and floors from dirt contacting moist surfaces and for the protection and comfort of the occupants11.
For pool areas, outside air is rarely replaced or supplemented by filtration, as air introduction is used to assist in controlling humidity and odors.
|
