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Riddle – What kills more Americans than AIDS, breast cancer, and auto accidents combined?

Imagine saving 100,000 lives per year. It’s doable, but how can we in the HVAC business do this? We are not medical professionals.

The usual and customary practice is for sick people to be admitted to a hospital and come out in better health than when they entered.

Throughout my childhood in Palacios, Texas, I spent time in all but one room of the Bayview General Hospital. Why was I not a victim of Hospital Acquired Infections (HAI)? Bayview had absolutely no HVAC of any kind. For most of the year, a wonderful breeze from over the Gulf of Mexico provided an inexhaustible supply of fresh air through hospital windows.

A report in the ISME Journal (26 Jan. 2012), Florence Nightingale wrote over 150 years ago that open windows are the hallmark of a healthy hospital ward. This observation distills down to a common HVAC process we call ventilation.

One hospital customer I service has had no outdoor air ventilation in the Emergency Room department. We discovered that although the outdoor damper actuator freely worked, it was doing nothing. Nada. Zip. When the original HVAC equipment was installed, the mechanical contractor installed a rectangular damper incorrectly sized in the outdoor air duct. One dimension of the damper was okay, it was the other that was substantially greater than the dimension of the duct; it was installed at an angle that assured its premature demise.

The ER AHU wasn’t the only area with no ventilation. We discovered several more. Our solution was to add a damper actuator to a balancing damper, remove the failed damper, install our in-house air flow measuring station. A programmable controller precisely now manages ventilation.

In one area, the laboratory, a test and balance (TAB) contractor certified the AHU had an outdoor air intake. The problem was this was not so. True, the damper was open, but no air was flowing because the high impedance of the outdoor air path was many times greater than the low impedance presented by the return air path.

We have a saying: To assume anything is to make an ass out of you and me.

Metrics, on the other hand, eliminate assumptions that can become deadly to patients.


We in the HVAC systems, especially we who provide the intelligence, can play a major role in the prevention and/or reduction of HAI through managed ventilation, precision control of temperature and relative humidity, and by creating reliable means to maintain pressure of specialized areas of the hospital.

John White

President, The Rockwall Company
info@rockwallcompany.com
(972) 771-3514