1. Sick Building syndrome-
Occupational Health
By 14.11.2004
 Dr.Ashok laddha
 Occupational Health
Physician
 MBBS, PGDC ,PGDD,
PGDEM, AFIH ,ACLS,BLS
 Diploma in Workplace
Health and safety. MBA-HA

2. Definition
 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
 a condition affecting office workers, typically marked
by headaches and respiratory problems, attributed to
unhealthy or stressful factors in the working
environment such as poor ventilation.

3. History
 In 1970-follwing the observations of Bensazak the attention
of medical profession was drawn to the development of
allergic respiratory disorder in employees working in AC
office
 Humidifier fever described by De weck in indoor(homes)
as well in industrial situation
 1976- out break of Legionnaire's disease in Philadelphia .
Due to contaminated cooling towers .several epidemics
have been reported worldwide
 The term "Sick Building Syndrome" was coined by WHO in
1986
 "Sick building" is therefore an expression used especially in
the context of workplace health.

4. Risk Factors
 Since the 1970s, researchers have tried to identify what
causes SBS. As yet, no single cause has been identified.
However, most experts believe that SBS may be the
result of a combination of different factors.

5. possible Risk Factors
 poor ventilation
 low humidity
 high temperature or changes in temperature throughout the day
 airborne particles, such as dust, carpet fibres or fungal spores
 airborne chemical pollutants, such as those from cleaning
materials or furniture, or ozone produced by photocopiers and
printers
 physical factors, such as electrostatic charges
 poor standards of cleanliness in the working environment
 poor lighting that causes glare or flicker on visual display units
(VDUs)
 improper use of display screen equipment
 psychological factors, such as stress or low staff morale

6. Chemicals in Indoor air
 chemicals commonly present in indoor air.
 benzene,
 carbon monoxide,
 formaldehyde,
 naphthalene,
 nitrogen dioxide,
 polycyclic aromatic hydrocarbons (especially
benzo[a]pyrene),
 radon,
 trichloroethylene and
 tetrachloroethylene,

8. Health effect of indoor chemicals
 Benzene is a genotoxic carcinogen in humans and causes
acute myeloid leukemia
 Exposure to carbon monoxide reduces maximum exercise
ability in healthy young individuals and reduces the time to
angina and, in some cases, the time to ST-segment
depression in people with cardiovascular disease,
 The principal health concerns of exposure to naphthalene
are respiratory tract lesions, and haemolytic anaemia in
humans
 Indoor nitrogen dioxide levels support the occurrence of
respiratory health effects
 lung cancer is the most serious health risk from exposure to
PAHs in indoor air.

9. Health effect of indoor chemicals
 Radon is classified by the International Agency for
Research on Cancer as a hu-man carcinogen
 Trichloroethylene—liver cancer
 Tetrachloroethylene ----impaired neuro-behavioural
performance and early renal changes.
 Formaldehyde—sensory irritation

10. Causes--1
 Inadequate ventilation
 Chemical contaminants
 Biological contaminants
 Electromagnetic radiation
 Psychological factors

11. Causes-2
 Poor and inappropriate lighting with absence of
sunlight,
 bad acoustics,
 poor ergonomics
 humidity may also contribute to SBS.

12. Sources--Chemical contaminants
 building exhausts—Bathroom /Kitchen
 Combustion byproducts form near by garbage
 motor vehicle exhaust
 poorly located air intake vents (lead paints, Radon,
formaldehyde, dust can enter through poorly located
air intake vents )
 volatile organic compounds (manufactured wood
products, pesticides, cleaning agents, Environmental
tobacco smoke, respirable particulate matter etc)

13. Psychological Factors
 Excessive work stress
 dissatisfaction,
 poor interpersonal relationships and
 poor communication are often seen to be associated
with SBS.

14. 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.

15. Sources--Biological contaminants
 pollen, bacteria, viruses, fungus, molds (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

16. Legionnaire's disease
 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

17. Humidifier fever
 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.

18. symptoms
 The symptoms of SBS may include:
 headaches and dizziness
 nausea (feeling sick)
 aches and pains
 fatigue (extreme tiredness)
 poor concentration
 shortness of breath or chest tightness
 eye and throat irritation
 irritated, blocked or running nose
 skin irritation (skin rashes, dry itchy skin)

19. Complications
 edema,
 palpitations,
 nosebleeds,
 cancers,
 pregnancy problems and miscarriages.
 Extrinsic allergic alveolitis,
 Legionnaire's disease,
 humidifier fever,
 pneumonia and occupational asthma

20. recovery time
 The symptoms can be clinically defined and have
clearly identifiable causes. The complainants may
require prolonged recovery time after leaving the
building.

21. Indicators of building related illness
 1. Building occupants complain of symptoms such as
cough; chest tightness; fever, chills, and muscle aches.
 2. The symptoms can be clinically defined and have
clearly identifiable causes.
 3. Complainants may require prolonged recovery times
after leaving the building

22. Investigation
 ‘walk-through’ inspection
 Establishing a cause and effect relationship between
symptoms and IAQ.
 Evaluation of IAQ
 Cause Identification
 Information collection (he Occupants,HVAC Systems
for pollution pathways and Possible contamination
sources.

23. CARBON DIOXIDE MEASUREMENTS
 CO2 READING (PPM) EFFECTS
 Below 600 Adequate fresh air – No complaints
 600 – 800 Occasional complaints esp. if air
temperature rises
 800 – 1000 Complaints more prevalent
 Above 1000 Complaints are common
 Carbon dioxide has a TLV-TWA of 5000 ppm and a
TLV/STELof 30,000 ppm

24. Comfort levels recommended-1
 Temperature (dry bulb)19-23°C
 Relative humidity (RH)40-70%More than 55% RH is
needed in carpeted buildings with under floor heating
to avoid electrostatic shocks
 VentilationDelivery of fresh air8 l/s/person
(minimum)
 16 l/s/person where some smoking
 25 l/s/person where heavy smoking

25. Comfort levels recommended-2
 Total air supply4–6 air changes/h
 Air speed0.1–0.3 m/s. Less than 0.1 m/s causes
stuffiness. More than 0.3 m/s causes draughts. For air
speeds higher than 0.1 m/s,
 Competent authority recommends an increase in air
temperature to take account of air movement
 Sound46 dBA is the upper limit for general office work
 Lighting500 lux for general office work, 750 lux for
deep-plan offices and work at drawing boards,
proofreading, etc.

26. routine five-point survey
 a walk-through inspection to look for sources of
contamination, such as photocopiers, insulation and
cleaning materials,
 measurement of temperature, humidity, air movement and
other comfort parameters,
 measurement of carbon dioxide to assess the ventilation
efficiency,
 measurement of formaldehyde, carbon monoxide, ozone
and respirable particles and
 examination of the ventilation system for causes of poor
distribution, including tests for biological organisms in any
water in the system

28. Treating the underlying problem
 Education and recognition of the problem.
 Addressing relevant psychosocial issues, eg high job
demands and low support.
 Removal of the pollution source if possible.
 Improved planning of building ventilation.
 Maintenance of indoor air quality by regular servicing
and quality measurements.
 Discouragement of Smoking
 Increasing the number of live plants in buildings.

29. Building biology
 Site status:The building site should be geologically
undisturbed. Residential areas should be away from
industrial centers and main traffic routes and housing
should have sufficient green space and should be in
harmony with the surrounding environment.
 Construction concepts: Natural, unadulterated and
nontoxic building material should be used, walls, floors
and ceilings should not be susceptible to mold or fungi, the
basement should be waterproof and well -ventilated, the
earth's natural magnetic field should not be altered or
distorted, production, installation and disposal of building
materials should not lead to environmental pollution,
building activities should not lead to exploitation of
nonrenewable, rate resources.

30. Building biology-2
 Interiors:Lighting and color must mix well with the
surroundings and not jar the senses, man-made electromagnetic
radiation must be reduced as much as possible, interiors should
be done by using natural materials without toxic content and
should be economically designed, there should be no toxic
outgases or harsh smells, indoor humidity should be naturally
regulated, air pollutants should be filtered and neutralized,
thermal insulation should be balanced with heat retention, use
of solar heating should be encouraged, moisture content in new
buildings should be low, protective measures against noise
pollution and harmful infrasonic and ultrasound radiation must
be ensured, natural balance of atmospheric electricity and ion
concentration should be maintained

31. PREVENTION AND CONTROL
 Removal or modification of the pollutant source
 Air cleaning
 Education and communication
 Increase the ventilation rates and air distribution
 Legislation
 Research

32. Pit fall
 Both the World Health Organization and the U.S.
Environmental Protection Agency recognize Sick
Building Syndrome and Building Related Illness as a
public health problem. Yet, because an environmental
illness is difficult to diagnose, can appear and
disappear seemingly at random, and often results in
lost time at work, many victims are branded
hypochondriacs or shirkers by employers, peers, and
even doctors.

33. Take home message
 "If we build, design, and operate our homes/office in a
healthy manner, we can keep a lot of these problems
from getting out of hand."