Ventilation continues to be a big concern at schools teaching K-12 students across the nation. How to deal with it is open to interpretation, and solutions can vary from changing filters, to installing new equipment to take care of the problem, to avoiding problems before they even start.

The Survey Says...

Heery International (Atlanta) a design, engineering, and construction management firm that has been involved in nearly 45,000 classroom projects, recently commissioned a survey to look at what impact the design and condition of school facilities have on teacher retention and learning.

Those surveyed included 1,350 teachers and principals in nine cities such as Atlanta, New York, Los Angeles, Houston, Baltimore/Washington, Dallas, Cleveland, San Francisco, and Seattle.

The results were hardly surprising. Sufficient heating and air conditioning were the two most important issues that affected the quality of education, followed by technology: 91% of respondents feel that these issues have a strong impact on the overall quality of education; 81% say it has a strong impact on self-esteem; and 71% say that classroom design and condition has a strong impact on test scores.

Specifically, teachers want the ability to control the temperature in their classrooms. According to the conclusions reached by the survey, “Several participants complain that they do not have the ability to control the temperature in their own rooms. When the heating and cooling are controlled at some central location, it is virtually impossible for a teacher to maintain a comfortable temperature in his or her room. And when teachers and students are uncomfortable, learning is difficult.”

This sentiment is echoed by an anonymous Atlanta teacher who said, “We have absolutely no control over the heating or air in our room. It’s controlled at a central panel in the front office. My room might be ... really cold and across the room it’s like a sauna. I think that’s kind of ridiculous.”

Humidity Breeds Mold, A Lot Of Mold

Paul Garrison, P.E., director of environmental services with Virginia Beach City Public Schools, has had several problems with high humidity in several schools, in general due to the fact that the buildings, on average, are only open for 180 days a year, and during that time there is a high concentration of people in the buildings. He is chiefly concerned with humidity control.

“We are required by code to provide a lot of outside air,” he said. “The trick is to provide enough ventilation, but moisture is being dumped into the air. Unfortunately, during our humid seasons, this outside air contains a lot of moisture that we are dumping into the buildings. It’s a catch-22 for us,” he said. Other problems encountered included outside air dampers that may not open properly.

To fix the problems at several schools in Garrison’s area, decoupled systems were installed: existing heat pumps were reused that provided only heating and cooling, teamed with separate rooftop units which provide the code-dictated amount of dehumidified, highly filtered outside air; dry, diluted air; and filtration.

One major problem was occurring every summer.

“Custodians will mop the floor and close up the school. When they come back [in the fall] everything is green,” Garrison said. This led to policy formation. “We developed guidelines to reduce humidity in unoccupied school buildings,” he said to thwart this mold growth.

Mold growth is what John Williams, Jr., a controls technician with Carrier, Inc. (Syracuse, NY), was faced with when a school called him to fix a ventilation problem in its library. “One hundred percent fresh air will cause books to mildew,” he said. The library in question lacked exhaust so he recommended a makeup air unit to fix the problem. “It was an easy, inexpensive fix,” he said.

Stale air, in William’s opinion, is the most common ventilation problem in schools. “Bacteria build-up develops on books and the old-style chalkboards.” Bacteria growth in schools is also a major concern for K. Scott Roberts, Honeywell Commercial Air Products (Niceville, FL).

Many schools have too few air changes per hour to provide comfort and these low ventilation rates don’t clean the air of germs and contaminants or provide adequate dehumidification, Roberts said. He recommends energy recovery ventilators that provide direct ventilation to the room and exhaust stale air, and using high-grade HEPA or gas-phase filters. “These control biocontaminants and mold and keep microbes in check,” Roberts said.

Tools For Schools = Community Involvement

The United States Environmental Protection Agency implemented a program in 1995 called “Indoor Air Quality Tools For Schools” which is designed to allow schools to instigate their own indoor air quality improvements.

According to Eugene Benoit, environmental engineer with the EPA, “[Tools for Schools] is a voluntary guide that schools can use to identify and prevent IAQ problems.” The program consists of a kit, which contains checklists for all school employees for various parts of the school such as classrooms, nurse’s offices and waste management, a step-by-step guide for coordinating the checklists, an Indoor Air Quality Problem Solving Wheel, a fact sheet on IAQ issues, and sample policies and memos.

The first step is to coordinate a walk-through of the building to identify problems, preferably with not only members of the school staff but parents as well.

This is crucial, said John W. Bitoff, director of facilities management, San Francisco Unified School District. “This program empowers the people at the site. The Tools For Schools kit shows the layperson what is wrong and how to fix it,” he stated. The program was used at two of his district’s schools, G.W. Carver and Charles Drew Elementary Schools, both of which had higher than average cases of respiratory ailments among students. In both cases, the inspection was a team effort.

The problems at these schools were easily fixed. In one instance, the heat generated from a copy machine in the same small room as a thermostat caused classrooms to be too cold. Other instances involved posters taped over thermostats, bookcases placed over intake vents, and general miscommunication; at one school, the custodian said he was told to shut the system off every morning.

Both schools received HEPA vacuums and a box of filters, for those cases in which the filters could be easily accessed and staffs could maintain them. This was a cost-effective solution, Bitoff said. Having school staff replace the filters wasn’t possible in every case, however, as some filters were in unreachable places. Saying that these were a “maintenance nightmare,” Bitoff admits, “We don’t change air filters as often as we should.” This is true for vents in the buildings as well due to lack of staff, he added.

This is a trend among schools nationwide. Bitoff said that maintenance staffs are shrinking while work keeps piling on. “I’m faced with 35 years of deferred maintenance,” he said. The numbers of custodians in buildings are also dwindling although they are limited in the work they are allowed to do, mainly cleaning, which also suffers. “If you can’t keep a school clean, then you add to the IAQ problem,” he said.

Since the Tools for Schools program was initiated at both schools, visits to the nurse’s office for asthma inhalers have dropped by at least half. Sixteen other schools in the district are implementing the program, eight of which have already had their walk-through inspections.

Another school that has had success with the Tools for Schools program is King-Murphy Elementary School in Colorado’s Clear Creek School District. The problems here were complex to say the least, said Art Benton, facilities and maintenance supervisor of the district.

“We didn’t have good IAQ. The ventilation system was not up to where it should be,” he said. The problems were myriad. When Benton came to the school, each classroom had an air conditioning unit, a unit ventilator, and an exhaust system. “So we were heating and cooling the rooms all at the same time,” he said.

Other problems included air conditioners that were freezing up and dripping into classrooms; units that had stopped working and others that had not worked properly from the time they were installed; air-handling units with disconnected dampers; and bus fumes entering through the outside air supply.

The King-Murphy inspection team consisted of parents, custodians, staff members, and even students. “Once we identified problems, we went about fixing them,” Benton said.

These fixes included entering into a district-wide performance contract; replacing the classroom systems with a single unit that provides fresh air, heating, and air conditioning; initiating a better preventive maintenance program; shopping around for cheaper, more efficient air filters; adjusting the dampers; and adding a timer to the dampers near the bus loading area.

Other fixes included tinting the windows, a lighting retrofit, and a district-wide policy of banning pets in classrooms, which was also a key for Bitoff, who did the same thing in his school district.

The fixes have worked, according to Benton. “We don’t have as many ill students, and it kept the teachers there, too. We got to involve everyone in the process,” he said.

The problems in all of these classrooms aren’t unique according to Timothy C. Lehman, P.E., a mechanical department coordinator with Fanning/Howey Associates, Inc. (Celina, OH). He said that most school districts have unit ventilators and one of the drawbacks is that coils freeze and intakes get backed up.

“The design of unit ventilators are kind of the problem,” Lehman said. “They are not designed to take in large quantities of outdoor air that is required by ASHRAE.” In the winter, the coils freeze, and in the warmer weather the coils allow too much humidity in the space.

Avoiding Problems Before They Start

During construction projects, the best way to fix these problems before they even start, according Clay Clayton, AIA, senior project manager at Heery is to know the abilities of the district. “Some districts can handle more technology. Designers design systems that school districts can’t afford to maintain or can’t handle technically.”

This was evident in two separate projects Clayton worked on in North Carolina. One district wanted individual units in case one broke down the whole system wouldn’t be affected, he said. The other district wanted one central unit because too many would have been too much to handle.

To that end, Clayton favors setting up design guidelines in concert with the maintenance staff and adapting the system to a school district’s needs and training.

On new construction projects, he recommends giving the staff a cursory training session. “In a new school, the first few weeks are difficult for staff,” Clayton says. Simple training to get the system up and running is perfect for overworked staff members. There is always time to come back later and train the staff on maintenance issues like changing filters.

And Once They Do...

The common sense approach to improving IAQ seems to start with listening to the concerns of the main users of the building and moving on from there. Once problems have been identified, many engineers can use creative and inexpensive ways to fix the problems. IAQ will probably always be a concern, but it needn’t become a problem.ES