Although it is difficult to
prove that specific health problems among indoor workers have particular causes,
Indoor Air Quality (IAQ) has become a real occupational health issue.
IAQ is a suspect when building
occupants experience one or several of the following symptoms: headaches, fatigue,
shortness of breath, sinus congestion, coughing, sneezing, dizziness, nausea,
and irritation to the skin, eyes, nose and throat. These symptoms can usually
be attributed to inadequate temperature, lack of humidity or lighting; exposure
to chemicals, dusts, gases, vapours and odours; or a lack of fresh air from
the ventilation system. People generally develop symptoms within a few hours
of starting the workday and feel better after leaving the building. Collectively,
these symptoms are often referred to as "Sick Building Syndrome."
The reason IAQ problems are
difficult to determine is that building occupants are exposed to not one but
several adverse conditions. For example, you might not think that the slight
emissions from furniture, carpets, photocopiers, or the perfume worn by your
co-workers could be harmful, but in combination they can affect your health.
Again, these effects are impossible to trace accurately, but the condition does
have a name: Multiple Chemical Sensitivity (MCS).
The following is a list of
common indoor air contaminants and their sources:
Carbon dioxide, tobacco
smoke, perfume, viruses, bacteria from building occupants
Gases, vapours, odours from furniture, carpets and paints
Dust, fibreglass, asbestos from building materials
Toxic vapours, volatile organic compounds from cleansers, solvents, pesticides,
Bacteria, spores, pollen, mites from damp areas and stagnant water
Ozone from photocopiers, electric motors, electrostatic air cleaners
It is possible to control these
contaminants by eliminating or isolating the source, or by maintaining a good,
clean heating, ventilating and air conditioning (HVAC) system. If the HVAC system
is functioning properly, it also regulates humidity, air velocity and temperature.
Consider the Total Indoor Environment.
Besides the quality of indoor air, Total Indoor Environment also includes temperature,
lighting and noise. In an office that is too warm, occupants feel tired; one
that is too cold causes occupants' attention to drift, making them restless
and easily distracted. Inadequate lighting affects people's vision. Loud or
irritating noises affect concentration. These are all factors which can contribute
to headaches, stress, and a variety of other problems.
You cannot take a tablet to
cure Sick Building Syndrome. The surest way to control
symptoms is to improve indoor air quality. It is often simply a matter of cleaning
an air filter, regularly replacing the slime in a humidifier with clean water,
or opening a window.
There are no occupational health
and safety regulations for IAQ, however the Canadian Building Code recommends
the American Society for Heating, Refrigeration and Air Conditioning Engineering
(ASHRAE) 62-1989 as a guideline for ventilation and ASHRAE 59 for thermal comfort.
Order your copy of CCOHS' Indoor
Air Quality Health and Safety Guide for details about indoor air contaminants,
and everything building occupants need to know about ensuring their health and