Outdoors, we're ever conscious of car and truck exhaust, factory smoke and windblown road dust, all factors that contribute to poor air quality. But indoor air can be just as harmful - particularly in schools.

Half of our country's 115,000 schools have problems linked to indoor air quality, according to the Environmental Protection Agency. Many of these buildings are old or poorly maintained, exposing students to a variety of hazards including dust, mold and toxic chemicals.

With nearly 55 million people spending their days inside elementary and secondary schools, unsatisfactory indoor air quality in schools is a significant public health concern. Exposure to allergens and respiratory irritants in indoor environments can cause severe allergic or asthmatic reactions. And poor environmental conditions in schools can inhibit learning and lower staff productivity.

Children are especially susceptible to indoor air pollution because of their lower body weights and fast breathing rates (which means they receive a higher pollutant dose per body weight than adults), and the fact that their breathing zones are much closer to the ground than those of adults, making them more susceptible to heavier airborne chemicals and settled dust.

A survey by the National Association of School Nurses found that asthma is more disruptive of school routines than any other chronic condition. And childhood asthma rates in New Hampshire are among the highest in the nation.

Thankfully, steps are being taken to address indoor air quality issues in New Hampshire. Last summer, Gov. John Lynch established a commission to study indoor air quality issues in the state's 470 public schools. The commission will study the feasibility of implementing indoor air quality standards and performing regular air quality inspections. It will also make recommendations regarding cost-effective, alternative initiatives to address air quality issues.

Nonetheless, more regulations or policies are needed that specifically address poor air quality for New Hampshire's 200,000 students. Parents and caregivers of children and adolescents in public schools should urge the Legislature and local organizations to address the factors and substances that contribute to environmental health problems in schools.

Individual schools should also be pushed to improve indoor air quality. Simple changes can make a big difference. Schools can minimize the amount of fleecy materials (curtain and fabric partitions) and papers and boxes, which collect and release pollutants (clutter also makes general cleaning more difficult); ensure that furniture, supplies and books aren't blocking ventilation units; and limit the number of throw rugs, pillows and stuffed animals, which serve as a breeding ground for dust mites and mold.

On a larger scale, programs that involve building walkthroughs to isolate problem areas in a building, "comfort" surveys and indoor air quality questionnaires are also beneficial.

Taking a proactive approach to managing school air quality will not only have a significant positive impact on a child's health and learning ability, but will save time and money by minimizing absenteeism, crisis intervention, breakdowns, energy use, and liability. It's imperative that New Hampshire's public schools become committed to maintaining safe and healthy indoor environments for both students and staff.

(Denise Brewitt is executive director of the Council for Children and Adolescents with Chronic Health Conditions, a New Hampshire organization that advises state agencies and the Legislature on chronic health-care issues impacting children and adolescents.)