SICK BUILDING SYNDROME
Sick building syndrome (SBS) is a phenomenon affecting building occupants who claim to 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. SBS is also used interchangeably with “building-related symptoms”, which orients the name of the condition around patients rather than a “sick” building. A 1984 World Health Organization (WHO) report suggested up to 30% of new and remodeled buildings worldwide may be subject of complaints related to poor indoor air quality.
Sick building causes are frequently pinned down to flaws in the heating, ventilation, and air conditioning (HVAC) systems. Other causes have been attributed to contaminants produced by outgassing of some types of building materials, volatile organic compounds (VOC), molds (see mold health issues), improper exhaust ventilation of ozone (byproduct of some office machinery), light industrial chemicals used within, or lack of adequate fresh-air intake/air filtration (see Minimum Efficiency Reporting Value).
Signs and symptoms of the building-related disease are as follows
Cough, chest pain, shortness of breath on mild exertion, edema, palpitations, nosebleeds, cancers, pregnancy problems and miscarriages. Extrinsic allergic alveolitis, Legionnaire’s disease, humidifier fever, pneumonia and occupational asthma are also known to occur.
Legionnaire’s disease is due to contamination of cooling towers by legionella organisms. Legionella is also responsible for Pontiac fever. Legionnaire’s disease occurs predominantly in the middle aged and elderly adults whereas Pontiac fever occurs in young healthy adults, and has a very high secondary attack rate.
Humidifier fever is caused by breathing in water droplets from humidifiers heavily contaminated with microorganisms causing respiratory infections, asthma and extrinsic allergic alveolitis. The disease is noninfective in nature. The patient may have flu-like symptoms. It is sometimes called Monday Fever. Permanent lung damage does not occur.
The symptoms can be clinically defined and have clearly identifiable causes. The complainants may require prolonged recovery time after leaving the building.
It is important to note that complaints may also result from other cause like a preexisting illness or other allergies, job-related stress or dissatisfaction and psychosocial factors.
The following are some of the factors that might be primarily responsible for SBS:
1. Chemical contaminants
1.1.From outdoor sources: Contaminants from outside like pollutants from motor vehicle exhaust, 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 enter a building from a nearby garage. Radon, formaldehyde, asbestos, dust and lead paint can enter through poorly located air intake vents and other openings.
1.2.From indoor sources: The most common contaminant of indoor air includes the volatile organic compounds (VOC). The main sources of VOC are adhesives, upholstery, carpeting, copy machines, manufactured wood products, pesticides, cleaning agents, etc. Environmental tobacco smoke, respirable particulate matter, combustion byproducts from stove, fireplace and unvented space heater also increase the chemical contamination. Synthetic fragrances in personal care products or in cleaning and maintenance products also contribute to the contamination.
2. Biological contaminants
The biological contaminants include pollen, bacteria, viruses, fungus, molds, etc. These contaminants can breed in stagnant water that has accumulated in humidifiers, drainpipes and ducts or where water has collected on ceiling tiles, insulation, carpets and upholstery.
Insect and bird droppings can also be a source of biological contamination. Biological contamination causes fever, chills, cough, chest tightness, muscle aches and allergic reactions. In offices with a high density of occupancy, airborne diseases can spread rapidly from one worker to another. Air-conditioning systems can recirculate pathogens and spread them throughout the building e.g., Legionnaire’s disease due to legionella organisms.[4,6]
3. Inadequate ventilation
In 1970, oil embargo led building designers to make buildings more airtight, with less outdoor air ventilation, in order to improve energy efficiency. The ventilation was reduced to 5 cfm/person. This reduced ventilation rate was found to be inadequate to maintain the health and comfort of building occupants. Malfunctioning heating, ventilation and air-conditioning systems (HVAC systems) also increase the indoor air pollution. In order to have an acceptable indoor air quality (IAQ) with a minimum energy consumption, The American Society of Heating, Refrigeration and Air-Conditioning Engineers (ASHRAE) recently revised ventilation standards to a minimum outdoor air flow rate of 15 cfm/person to avoid the problems related to inadequate ventilation. The standards are 20 cfm/person in office spaces and 60 cfm/person in smoking lounges. Poor design and construction of buildings with more number of offices cramped in a building to increase the salable area also contribute to inadequate ventilation.
4. Electromagnetic radiation
Gadgets like microwaves, televisions and computers emit electromagnetic radiation, which ionizes the air. Extensive wiring without proper grounding also creates high magnetic fields, which have been linked to cancer.
5. Psychological factors
Excessive work stress or dissatisfaction, poor interpersonal relationships and poor communication are often seen to be associated with SBS.
6. Poor and inappropriate lighting with absence of sunlight, bad acoustics, poor ergonomics and humidity may also contribute to SBS.
The symptoms of SBS are commonly seen in people with clerical jobs than in people with managerial jobs because professionals or managers have better working conditions. The symptoms are more common in females than in males probably because more females are in secretarial jobs, they are more aware of their health or a lesser dose of pollutants is required to manifest the effects. The symptoms are more common in air-conditioned buildings than in naturally ventilated buildings and are more common in a public sector building than in a private sector building