Appendix C 417
Non-specific health symptoms are a distraction from work and
can lead to absence from work (Preller et al. 1990) and visits to doc-
tors. When problems are severe and investigations of the building are
required, there are financial costs to support the investigations and
considerable effort is typically expended by building management staff,
by health and safety personnel and by building engineers. Responses
to non-specific health symptoms have included costly changes in the
building.
4.6.2 Building-Related Illness
In contrast to non-specific health symptoms, the term building
related illness (BRI) is sometimes used to describe a specific building-
related health effect with known causes and objective clinical findings.
Examples of BRIs include Legionnaires Disease, hypersensitivity pneu-
monitis, lung cancer from radon exposure, and health effects known to
be a consequence of exposures to specific toxic compounds in buildings.
Allergies and asthma are considered by some to be building related ill-
nesses.
4.7 SENSITIVE POPULATIONS
Significant subsets of the total population have an increased
sensitivity to indoor pollutants. Approximately 20% of people have en-
vironmental allergies and approximately 10% experience asthma (Com-
mittee on Health Effects of Indoor Allergens 1993). Peoples sensitivity to
chemical irritants and their ability to detect odors also vary. To maintain
low levels of building-related health complaints and health effects, the
indoor environment must be maintained satisfactory for a substantial
majority of occupants, many of whom are more sensitive than the aver-
age person to indoor pollutants.
A very small portion of the population report severe health ef-
fects when exposed to extremely low concentrations of a large variety
of chemicals in the air. Their very high sensitivity to these chemicals
may follow a period of sensitization caused by exposure to a higher
concentration of one or more chemicals. The term multiple chemical
sensitivity (MCS) is commonly used to describe this phenomenon. There
is considerable uncertainty and controversy within the medical commu-
nity about the concept of MCS. The current state of knowledge about
MCS and its causes, physiological and psychological, is very limited.
Owners and operators of buildings and building design and energy