Symptoms and microenvironmental measures in nonproblem buildings.

Symptoms commonly defined as the sick building syndrome were studied in a cross-sectional investigation of 147 office workers in five building areas using a linear-analog self-assessment scale questionnaire to define symptoms at a specific point in time. At the same time, the environment in the breathing zone was characterized by measuring thermal parameters (dry-bulb temperature, relative humidity, air speed, and radiant temperature), volatile organic compounds, respirable suspended particulates, noise and light intensity, and carbon dioxide and carbon monoxide levels. Demographic characteristics of the occupants and building characteristics were recorded.

Precipitation: its acidic nature.

A comparison of the free hydrogen ion concentration and the total hydrogen ion concentration of rain samples shows that rain is a weak acid. The weak acid nature of rain casts doubt on the concepts that the acidity of rain is increasing and that these increases are due to strong acids such as sulfuric acid.