Skip to main content

Control strategies for indoor air quality

Short answer

The main strategies are source control, ventilation and air cleaning. Source control, by eliminating or substituting pollutants, is most effective; ventilation supplies fresh outdoor air; air cleaning with filters or adsorbents supplements the other methods.

Explain the main strategies used to control indoor air pollution.

Three basic strategies are used, in order of effectiveness: source control, ventilation, and air cleaning.

1. Source control (best and most economical)

  • Eliminate the source, e.g. ban smoking, use only lead-free paints, avoid asbestos.
  • Substitute with low-emission products: low-VOC paints, formaldehyde-free boards, electric or LPG stoves.
  • Modify the source: seal radon entry cracks, enclose asbestos, let new furniture off-gas outdoors, and vent combustion appliances outside through flues and hoods.
  • Keep humidity below 60% to prevent mould, and fix leaks.

2. Ventilation

  • Natural: windows, vents, and the stack effect.
  • Mechanical: exhaust fans in kitchens and toilets; supply and exhaust fans with heat recovery.
  • Supply enough outdoor air per person according to ventilation standards (for example, 8-10 L/s per person is typical).
  • Place the air intake away from outdoor pollution (traffic, exhausts).

3. Air cleaning

  • Particle filters: fibrous filters, HEPA filters (99.97% of 0.3 μ\mum particles), electrostatic precipitators.
  • Gas removal: activated carbon adsorption for VOCs and odours.
  • Cleaners treat only part of the air and do not remove all gases, so they supplement the other two methods.

Other measures

  • Regular maintenance and cleaning of HVAC systems, testing houses for radon, carbon monoxide detectors, and good housekeeping (wet cleaning, no dust traps).

✓ Answer checked by Claude Opus 5.5 (high effort)

Related questions

All Environment and Pollution Control chapter 3 questions →