제  목 : Sick Building Syndrome
  일  자 : 1998년 09월
  제공처 : Internet

                    Sick Building Syndrome
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    What Is Sick Building Syndrome?

    Sick building syndrome (SBS) is a situation in which occupants of a
    building experience acute health effects that seem 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.

    Frequently, problems result when a building is operated or maintained in
    a manner that is inconsistent with its original design or prescribed
    operating procedures. Sometimes indoor air problems are a result of poor
    building design or occupant activities.

    What Are the Symptoms of SBS?

    Building occupants complain of symptoms associated with acute discomfort.
    These symptoms include headaches; eye, nose, and throat irritation; a dry
    cough; dry or itchy skin; dizziness and nausea; difficulty in concent-
    rating; fatigue; and sensitivity to odors. With SBS, no clinically defined
    disease or specific chemical or biological contaminant can be determined
    as the cause of the symptoms. Most of the complainants feel relief soon
    after leaving the building.

    SBS may also reduce worker productivity and increase absenteeism.

    What Causes SBS?

    While specific causes of SBS remain unknown, the following have been cited
    as contributing factors to sick building syndrome. These elements may act
    in combination or may supplement other complaints such as inadequate
    temperature, humidity, or lighting.

      Chemical contaminants from outdoor sources: Outdoor air that enters a
      building can also be a source of indoor pollution. Pollutants from motor
      vehicle exhausts, plumbing vents, and building exhausts (bathrooms and
      kitchens) can enter the building through poorly located air intake vents,
      windows, and other openings. Combustion byproducts can also enter a
      building from a nearby garage.

      Chemical contaminants from indoor sources: Most indoor air pollution
      comes from sources inside the building. For example, adhesives,
      upholstery, carpeting, copy machines, manufactured wood products,
      cleaning agents and pesticides may emit volatile organic compounds (VOCs)
      including formaldehyde. Research shows that some 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 in some individuals. Environmental tobacco smoke and
      combustion products from stoves, fireplaces and unvented space heaters
      all can put chemical contaminants into the air.

      Biological contaminants: Biological contaminants include pollen,
      bacteria, viruses and molds. These contaminants can breed in stagnant
      water that has accumulated in humidifiers, drain pans, and ducts, or
      where water has collected on ceiling tiles, insulation, or carpet.
      Biological contaminants can cause fever, chills, cough, chest tightness,
      muscle aches, and allergic reactions. One indoor air bacterium,
      Legionella, has caused both Pontiac Fever and Legionnaire's Disease.

      Inadequate ventilation: In the 1970s the oil embargo led building
      designers to make buildings more air tight, with less outdoor air
      ventilation, in order to improve energy efficiency. These reduced
      ventilation rates have been found to be, in many cases, inadequate to
      maintain the health and comfort of building occupants.

    What Are the Solutions to Sick Building Syndrome?

    Solutions to SBS problems usually include combinations of the following
    measures:

      Increasing the ventilation rates and air distribution is often a
      cost-effective means of reducing indoor pollutant levels. At a minimum,
      HVAC systems should be designed to meet ventilation standards in local
      building codes. Make sure that the system is operated and maintained to
      ensure that the design ventilation rates are attained. If possible, the
      HVAC system should be operated to the American Society of Heating,
      Refrigerating and Air-Conditioning Engineers (ASHRAE) Standard 62-1989.
      If there are strong pollutant sources, air may need to be vented
      directly to the outside. This method is especially recommended to remove
      pollutants that accumulate in specific areas such as restrooms, copy
      rooms, and printing facilities.

      Removal or modification of the pollutant source is the most effective
      approach to solving a known source of an IAQ problem, when this solution
      is practicable. Ways to do this include: routine maintenance of HVAC
      systems; replacing water-stained ceiling tiles and carpets; banning
      smoking or providing a separately ventilated room; venting contaminant
      source emissions to the outdoors; using and storing paints, solvents,
      pesticides, and adhesives in closed containers in well-ventilated areas;
      using those pollutant sources in periods of low or no occupancy; and
      allowing time for building materials in new or remodeled areas to
      off-gas pollutants before occupancy.

      Air cleaning has some limitations, but it can be a useful addition to
      source control and ventilation. Air filters are only effective at
      removing some of the pollution, not all.

      Education and communication are important parts of any air quality
      management program. When everyone associated with the building, from
      occupants to maintenance, fully understands the issues and communicates
      with each other they can work more effectively together to prevent and
      solve problems.

    For More Information...

    Browse EPA's Indoor Air Website.

    For more information, contact a specialist at (800) 557-2366 or send us an
    E-mail message.

                  Environmental Health Center
           A Division of the National Safety Council
 1025 Connecticut Avenue, NW, Suite 1200, Washington, DC 20036
           (202) 293-2270 (tel); (202) 293-0032 (fax)