To prevent many of the common indoor problems due to biological agents, measures should be taken to ensure that:

• excess humidity and condensation are not present;
• surfaces are kept free of dust;
• stagnant water sources, such as humidifier tanks, are kept clean and occasionally disinfected;
• a high standard of appropriate personal hygiene is maintained.

It is recommended that exposures resulting from the use of consumer products be kept to a minimum by ensuring adequate ventilation and observing any other precautionary measures described on the product label and in any accompanying information. Pest control products should be used only when absolutely necessary.

Precautions should be taken to minimize inhalation of, and skin contact with, mineral fibres during home renovations and installation operations. Materials and products containing fibres should also be examined periodically for signs of deterioration. Advice should be sought before removing or damaging any materials thought to contain asbestos.

In order to minimize the exposure of people, and especially children, to lead of airborne origin, it is recommended that surfaces that may be contaminated be cleaned frequently and that a high standard of overall cleanliness be maintained.

Exposure to PAHs indoors should be kept to a minimum by:

• ensuring that any combustion systems, for example wood- and coal-burning stoves, are properly installed and maintained and operated under conditions of satisfactory ventilation;
• adhering to the guidelines and recommendations given in this document for particulate matter and tobacco smoke.

In view of the carcinogenic properties of tobacco smoke, any exposure to tobacco smoke in indoor environments should be avoided.