“Pool
and spa areas should be maintained
at a negative pressure of 0.05 to 0.15
in. of water relative to adjacent areas
of the building to prevent moisture
and chloramines odor migration. Active
methods of pressure control may prove
more effective than static balancing
and may be necessary where outdoor
r is used as part of an active humidity
control strategy. Openings from the
pool to other areas should be minimized
and controlled. Passageways should
be equipped with doors with automatic
closers to inhibit migration of moisture
and air.”
Many
people are not familiar with the term “Negative
Pressure”. So
let’s try to simplify this! Your
home is under positive pressure; a
poolroom is under negative pressure.
Have you ever walked into a hotel lobby
to check in, and smelled chlorine.
You haven’t seen the pool, but
you know one is there in the building
somewhere.
This is due to the poolroom not being maintained under a slight negative
pressure, so when you open doors into the pool room, the pool room environment
STAYS IN THE POOL ROOM, IT DOESN’T MIGRATE INTO OTHER AREAS.
Secondly,
vapor or water pressure tends to “pressurize” into
walls and ceiling in pool environments. You
may see drywall sagging or wet, ceiling
tiles falling down, ceilings caving
in, etc. due to moisture migration
and saturation of the building materials
and structure. Using negative pressure
along with dehumidification can help
prevent these problems.
Negative
Pressure can be accomplished in two ways:
(1) Using the outdoor air method
(bring in the required amount of cfm/outside air
per ASHRAE, exhaust the same amount and add more
cfm to create negative pressure). EPS will size
all of this for the client.
(2) Installing a negative
pressure fan in any outside wall of the pool room.
This is a continuous running fan installed on any
wall of the pool room that exhausts outside
Contact EPS Engineering for assistance or details at 800-671-9629 or 248-634-7562.
EPS is the home of DRY-AIR & VERI-DRY. We provide Design, Engineering, Consulting and Manufacturing for Residential and Commercial Indoor Swimming Pool Applications.
