Needles Hall is considered by UW Safety personnel to be the worst in terms of air quality. During the winter, low levels of carbon dioxide, temperature, and humidity are indicators of poor indoor air quality. The opposite is true during spring and fall, where high levels are the sources. On request by campus officials, UW's basements have been checked for excessive levels of radon. Levels are considered to be within the legal limit.
Asbestos is a non-flammable mineral product once used for insulation and fire proofing.
Where possible, all asbestos previously used has been removed, and all existing asbestos is maintained. In areas containing asbestos there must be a label indicating the presence of the substance. In the community of Waterloo there is significant concern for water quality. Waterloo obtains all of its water from groundwater resources, thus any contamination of surface flows creates a legitimate concern. According to health regulations, drinking water in Waterloo and at UW is acceptable, and is tested by the Ministry of Health when complaints are made.