With outdoor humidity rates near a constant 100% during the summer months, Houston, Texas is quickly becoming recognized as one of the world’s moldiest cities. Many of the area’s insurance carriers have seen a significant increase in mold claims in recent years, and in the past two years alone, carriers have paid more than $1 billion in mold settlements.

While virtually all types of buildings and structures in Houston are susceptible to mold growth, area schools are among the most affected. Especially those that allow fresh air in on a regular basis. Such was the case with the Montgomery elementary school in North Houston. With tropical rainforest-like air constantly infiltrating the classrooms of this 30-year-old structure, signs of mold growth, which had long been inevitable, started to surface in late 2001.

“There were some visible indications of mold in certain areas, and some of the classrooms smelled like a dirty wet sock,” explains Kyle Jeane, a HVAC technician with Houston-based Hal Watson A/C Co. “In addition, kids with asthma were becoming affected.” In addition to exacerbating asthma, the mycotoxins that mold spores produce are known to be responsible for other problems, from suppression of the immune system to neurological damage. Jeane was called in by school officials to investigate the situation. More specifically, he was asked to gather data on classroom humidity rates, and, based on this information, make recommendations on a dehumidification solution. To do so, he would need to set up dehumidifiers in a few classrooms, and provide analytical data that shows the difference in humidity between a classroom with a dehumidifier, and one without.

“While you could easily feel the difference in humidity with dehumidification, the school’s budget approval process made it necessary to show actual results based on analysis,” said Jeane. “This data would ultimately have to be presented to school architects, engineers, and the school board itself.” To record and analyze classroom climate conditions, Jeane relied on HOBO® H8 data loggers from Onset. These are compact, battery-powered devices that are used for continuous monitoring of temperature, relative humidity, light intensity, and other environmental conditions. Using a paperclip on a nail, Jeane was able to simply hang a logger on the wall in both the humid and dehumidified classrooms. Once mounted, the loggers started recording temperature, relative humidity, and dew point at 30-minute intervals.

After logging classroom conditions for three days, Jeane removed the loggers and offloaded the data onto a computer. For graphing and analysis, he used BoxCar Pro, an easy-to-use, Windows-based software program that accompanies HOBO data loggers.

“The software was very user-friendly, and it only took a few minutes to get all the data collected into nice graphical charts,” he explains. “From the charts, we could immediately see a dramatic split in terms of humidity rates in the two classrooms. The classroom with the dehumidifier was running at 45% humidity, while the other was closer to 95%. This was tangible evidence that our dehumidifiers were able to override the high dew points and pull the humidity down to a safe level.”

Jeane proceeded to print out the graphs and then presented his findings to school officials. Upon reviewing the results, the school was quick to approve funding for 15 Thermastor 150H humidifiers, which were installed soon thereafter. The school classrooms now have dial-stats on the wall, encased in a lock-box, and each is set to 45% humidity. Mold growth has become a “non-issue,” and the school air feels and smells clean and fresh.

Jeane attributes a large part of the success of the project to HOBO data loggers. “I’ve known about mold growth in buildings for a long time, but the consumer awareness really hasn’t been there until a few years ago. Now, with all the noise about Sick Building Syndrome, consumers are very aware. Data loggers do a great job of relating to people what’s going on inside their buildings, and they don’t lie. I consider them an extremely important tool in being able to monitor and diagnose these types of problems.”

For more information about data loggers, please contact Onset Computer Corporation at 1-800-LOGGERS, or visit www.onsetcomp.com.


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