What Causes Sick Buildings?

Sick Building Syndrome Can Be Prevented

The term "sick building syndrome" (SBS) is used to describe situations in which building occupants experience acute health and comfort effects that appear to be linked to time spent in a building, but no specific illness or cause can be identified.

The complaints may be localized in a particular room or zone, or may be widespread throughout the building.

Symptoms of Sick Building Syndrome may include:

  • Itchy, irritated, dry or watery eyes
  • Nasal congestion
  • Throat soreness or tightness
  • Dry itchy skin or unexplained rashes
  • Headache, lethargy, or difficulty concentrating.

Some building-related factors, such as high building temperature, poor ventilation, high humidity, and sealed windows, in tandem with introducing conventional paints, coatings and furnishings into the space, can contribute to SBS.

Causes of Sick Building Syndrome

  1. Inadequate Ventilation. Since the dawn of air conditioning and heating systems, building ventilation standards called for approximately 15 cubic feet per minute (cfm) of outside air for each building occupant.

    However, thanks to the 1970's oil crisis, national energy conservation measures called for a reduction in the amount of outdoor air provided for ventilation to 5 cfm per occupant to save energy.

    While lower ventilation rates did save energy, in many cases these reduced outdoor air ventilation rates were found to be inadequate to maintain the health and comfort of building occupants and people started getting sick from buildings in droves. During this time, the trend was to incorporate sealed windows and not allow occupants to control the ventilation in their spaces.

    The group that develops standards for heating, ventilating, and air conditioning (HVAC) systems, the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) developed its ventilation standard to strike a balance between energy efficiency and adequate ventilation to prevent sickness. So, twenty plus years later, we are back to providing a minimum of 15 cfm of outdoor air per person and 20 cfm/person in office spaces.

    Now, some spaces, depending on use, require even more fresh air. Densely occupied spaces such as gymnasiums or high pollutant use types such as laboratories or smoking lounges (where do you even see these nowadays?) require ventilation rates of up to 60 cfm per occupant.

    If you're really interested in this, take it up with your local mechanical engineer and/or spend some time with ASHRAE Standard 62 404.

  1. Chemical Contaminants From Indoor Sources. Have you ever considered that every paint, adhesive, carpet, upholstery, manufactured wood product, copy machine, pesticide, and cleaning agent bring a whole (unhealthy) host of chemicals into our spaces? We breathe these in every day.

    Toxins emitted from these products (unless they are certified as low-emitting by a third-party certification program) include volatile organic compounds (VOCs), including formaldehyde.

    Smoking contributes high levels of VOCs, other toxic compounds, and respirable particulate matter. VOCs can cause chronic and acute health effects at high concentrations, and some are known carcinogens. Low to moderate levels of multiple VOCs may also produce acute reactions.

    Combustion products such as carbon monoxide, nitrogen dioxide, as well as respirable particles, can come from unvented kerosene and gas space heaters, woodstoves, fireplaces and gas stoves. Eek! We are exposing ourselves to these toxins every single day.

  1. Outdoor Chemical Contaminants. Just the other day I witnessed smokers standing beside the outdoor air intake, blowing tobacco smoke straight into the 'fresh air' system of the building. Think of the drive through operator at McDonald's and you've got yourself a perfect example of idling vehicles and people inside the window directly breathing chemical contaminants.

    The outdoor air that enters a building can be a source of indoor air pollution. Other examples, include plumbing vents and building exhausts and can enter the building through poorly located air intake vents, windows, and other openings. In addition, combustion products can enter a building from a nearby garage. Not good for our health!

  2. Natural, Biological Toxins. Bacteria, molds, pollen, and viruses are types of biological contaminants. These contaminants may breed in stagnant water that has accumulated in ducts, humidifiers and drain pans, or where water has collected on ceiling tiles, carpeting, or insulation. Sometimes insects or bird droppings can be a source of biological contaminants.

    Physical symptoms related to biological contamination include cough, chest tightness, fever, chills, muscle aches, and allergic responses such as mucous membrane irritation and upper respiratory congestion. One indoor bacterium, Legionella, has caused both Legionnaire's DiseaseĀ and Pontiac Fever.

    These elements may act in combination, and may supplement other complaints such as inadequate temperature, humidity, or lighting. Even after a building investigation, however, the specific causes of the complaints may remain unknown.

    So what is a guy or gal to do?