Keep The Doors Closed


As swimmers and coaches, we have all been there…during a busy practice or meet, the air quality gets rough, and someone props open an outside door to let fresh air in. The cooler air provides relief for those near it, and some people even put fans in front of the doors to move the air further into the pool. It makes sense, right?

Wrong. But hey, when we were coaches and lifeguards, we opened doors too; we didn’t know any better. This message today is for anyone who opens doors to their indoor pool, especially in the winter time. Please stop doing it…opening doors is making the air quality worse.

It sounds odd to say that, doesn’t it? The truth is, the little bit of outside air you’re introducing into the natatorium is usually causing more harm than good, for several reasons. When it’s cold outside, the air you’re bringing in through the doors is unconditioned, and therefore adds a tremendous amount of stress on the building’s HVAC system. As swimmers and coaches, however, you probably think like we do—health is far more important than the efficiency of an HVAC system. We believe everyone deserves to breathe healthy air, and that the aquatics and HVAC industry experts have a moral imperative to deliver it to all pool users. The problem is, opening doors does far more than just stress the HVAC system…it creates more airborne pollution.

If you have read our articles on SwimSwam, you know that chloramine related air quality issues are inevitable, and caused by basic chemistry and air physics. Opening doors complicates the air physics, by encouraging faster evaporation of the pool water.  Cold air lowers the vapor pressure pushing down against the pool water, which allows for a faster rate of pool evaporation.  With more evaporation comes more chloramines, and thus begins a vicious cycle of bad air quality.

In summary, we know that opening doors makes those near it feel better, and provides some short term relief for swimmers and coaches on deck. But in reality, it’s doing more harm than good by not only stressing the HVAC system, but also increasing the rate of chloramine pollution in the air. There is a better way to handle these issues, and we encourage you to research the affects of bad air quality for yourself.