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Healthy School Indoor Environments Winter E-Newsletter

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Healthy School Indoor Environments | Winter 2016 E-Newsletter

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Winter Is Coming: Seasonal Tips to Maintain Your School Facilities.

In many areas of the United States, colder weather means spending more time indoors, making indoor air quality (IAQ) even more of a concern. On average, schools are more crowded than many other indoor spaces—they often have four times the population density of a typical office—and they house a larger proportion of children. Good IAQ is an important component of a healthy indoor environment and can improve students’ health. Critical for healthy IAQ in schools are quality design, operation and maintenance of heating, ventilation and air conditioning (HVAC) systems. Properly functioning HVAC systems provide adequate ventilation, control temperature and humidity to provide thermal comfort, control odors, and reduce the pollutants that cause most IAQ problems inside school buildings. Regular HVAC maintenance helps save energy and improve occupant health and performance. 

Six Tips to Prepare Your HVAC System for Winter:

  • Clear exterior HVAC systems of ice or snow; clean interior HVAC elements on a regular schedule. Poorly maintained HVAC units can lead to IAQ problems, including mold issues. Microbial growth in drip pans, ductwork, coils and humidifiers can both disrupt the HVAC system and affect building occupants’ health.
  • As temperatures fall, maintain indoor humidity levels. As the temperature outdoors drops, schools should be aware of indoor humidity levels. To protect occupant health and comfort as well as the school building and its facilities, indoor relative humidity should be maintained above 30 percent—ideally between 30 percent and 50 percent.
  • Ensure air filters are changed on a regular schedule. Air filters should have a dust-spot rating between 35 percent and 80 percent or a minimum efficiency rating value (MERV) between 8 and 13, depending on the compatibility of the air handling unit. The higher the MERV rating, the more particulates will be filtered, resulting in cleaner air.
  • Adjust HVAC operation for fall or winter conditions as needed to ensure proper ventilation. Provide outdoor air ventilation according to ASHRAE standards or local code. There are significant spatial and seasonal variations in the volume of air delivered by most HVAC systems, so systems may need to be adjusted. Learn more by checking out the ASHRAE Standard 62-2016. Exit
  • Adjust your maintenance schedule to take holidays into account. To ensure that HVAC systems are functioning properly over winter and holiday breaks, consider creating a holiday maintenance schedule. With intermittent building occupancy over breaks, outdoor air ventilation rates may need to be adjusted. Check that air registers are not inadvertently obstructed by furniture or large objects that may have been moved.
  • Activate the frost control option on Energy Recovery Ventilation (ERVs) systems as appropriate. Be wary of frost. In colder climates, some operating conditions can cause freezing within the energy recovery heat exchanger, and it is often necessary to equip energy-recovery ventilator (ERV) systems with a frost control option.

Additional Resources:

  • Download and use the IAQ Tools for Schools Ventilation Checklist. Tailor it to fit the needs of your individual school or district.
  • Watch selections from EPA’s IAQ Master Class Professional Training Webinar Series, such as Fresh Air: Optimal HVAC Management for Improved IAQ and Health and Mold and Moisture: Double Trouble for Schools for additional information on how to create healthy learning environments in the winter.
  • Download and use EPA’s new School IAQ Assessment Mobile App. This tool works alongside the IAQ Tools for Schools Action Kit and provides handy digital checklists for on-the-go school walkthroughs.
  • Review ASHRAE’s ventilation standards in more detail. School HVAC systems should be designed and operated to provide a minimum outdoor air ventilation rate consistent with current ASHRAE Standard 62.1. ExitFor classrooms, this standard is about 15 cubic feet per minute (cfm) of outdoor air per person.

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Keep Those Pests out of School this Winter (and Year-Round!) with Integrated Pest Management

Cockroaches, rodents and other pests found in school facilities can be hazardous to student and staff health. Cold winter weather encourages these pests to seek refuge indoors. If schools are not prepared, pests can find their way into school buildings and cause health problems for the occupants. Some pests can spread harmful pathogens. Many pests also are common sources of allergens, which can result in serious allergic reactions and trigger asthma attacks. More than 6 million children have asthma, and 80 percent of asthma in children is caused by allergens[1],[2]. Thirty-seven percent of children with asthma in the United States are allergic to cockroach allergens and are more likely to require medical attention for asthma-related issues[3]. To maintain healthy IAQ, schools can control pests and reduce exposure to chemicals by implementing an integrated pest management (IPM) program.

IPM is a smart, sensible and sustainable approach to controlling pests. IPM takes advantage of all appropriate pest management strategies, including the judicious use of pesticides. In contrast to conventional pest management, which controls existing pests through scheduled pesticide applications, IPM controls pest populations by removing their basic survival elements, such as food, water and shelter, and by blocking access to facilities where these items might be readily available. IPM prevents pest problems before they begin and cultivates healthy school environments by reducing the unnecessary exposure of students, teachers and staff to pests and pesticides.

Conduct a walkthrough using the IAQ Tools for Schools IPM Checklist, which will help identify potential problem areas and pest entry areas. Know your common school pests. Each pest has its own attributes, and the key to conducting good IPM is understanding the pests involved. House mice, for example, can fit through about ½-inch gap, produce about 40 to 100 fecal pellets a day, and give birth to as many as 150 young each year[4]. Pests can produce conditions that are fire hazards, such as chewing through electrical wires. Openings to the outdoors provide easy entry for pests; seal all gaps and entries in your school’s building envelope to eliminate pest access and harborage. Once all entry ways have been sealed, safely eliminate existing pests using basic IPM principles, including—

  • Inspect and monitor for pests.
  • Establish or refer to an IPM plan.
  • Use baits instead of pesticide sprays.
  • Communicate with occupants prior to pesticide use.
  • Mark indoor and outdoor areas treated with pesticides.

Additional Resources:

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The IAQ Knowledge-to-Action Professional Training Webinar Series Is Now Available On-Demand!

The IAQ Knowledge-to-Action Professional Training Webinar Series comprises four 1-hour technical, core-competency, Web-based trainings that demonstrate how the knowledge gained in the IAQ Master Class Professional Training Webinar Series can be translated into actions that improve or sustain an IAQ management program within your school or school district. This webinar series is now completely available on-demand! Refresh your technical IAQ knowledge or add to your IAQ expertise with these webinars. Learn from technical experts and benefit by earning AIA continuing education credits from each webinar. Share this series with your colleagues or with other school districts and help spread knowledge that can assist schools in creating IAQ management programs that protect school occupants. Healthier school air means healthier students, faculty and staff.

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Spotlight on a IAQ Schools Resources: Virtual Trainings

Upcoming Energy Savings Plus Health Webinar
Energy Efficiency Plus Indoor Air Quality: Strategies for Improving Health and Reducing Energy Costs in Your School Exit
Date: Thursday, January 26, 2017
Time: 1:00 pm – 2:00 pm ET

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[1] CDC (U.S. Centers for Disease Control and Prevention) National Center for Health Statistics. 2015. “Asthma.” Last modified October 6, 2016.

[2] Breysse, P. N., et al. 2005. “Indoor Exposures to Air Pollutants and Allergens in the Homes of Asthmatic Children in Inner-City Baltimore.” Environmental Research 98(2): 167–76.

[3] Gore, J. C., and C. Schal. 2007. “Cockroach Allergen Biology and Mitigation in the Indoor Environment.” Annual Review of Entomology 52: 439–63.

[4] National Pest Management Association. 2016. “Eight Fascinating Facts You Never Knew about Mice.” Last modified 2016.

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