Indoor Air Quality Unit-VIII

1. Indoor Air Quality
Unit-VIII

2. Indoor Air Quality Management
• Indoor Air Quality (IAQ) is a term which refers to the
air quality within and around buildings and
structures, especially as it relates to the health and
comfort of building occupants.
• IAQ refers to the quality of the air inside buildings as
represented by concentrations of pollutants and thermal
conditions that affect the health and performance of
Occupants.
• It refers to the nature/ quality of the conditioned
(heat/cool) air that circulates throughout closed space/
area, where we work and live and breath the air.

3. Indoor Air Quality Management

4. Indoor Air Quality Management
• IAQ can be affected by gases (including carbon
monoxide, radon, volatile organic compounds),
particulates, microbial contaminants (mold,
bacteria) etc.

5. Indoor Air Quality Management
• Source control, filtration and the use of
ventilation to dilute contaminants are the
primary methods for improving indoor air
quality in most buildings. Residential units can
further improve indoor air quality by routine
cleaning of carpets and area rugs.

6. Indoor Air Quality Management

7. Common Pollutants
• Second-hand smoke is tobacco smoke which
affects other people other than the 'active' smoker.
Second-hand tobacco smoke includes both a
gaseous and a particulate phase, with particular
hazards arising from levels of carbon monoxide
and very small particulates (at PM2.5 size) which
get past the lung's natural defenses. The only
certain method to improve indoor air quality as
regards second-hand smoke is the implementation
of comprehensive smoke-free laws.

8. Second-hand Smoke

9. Common Pollutants
Radon
• Radon is an invisible, radioactive atomic gas
that results from the radioactive decay of
radium, which may be found in rock formations
beneath buildings or in certain building
materials themselves. Radon is probably the
most pervasive serious hazard for indoor
air, probably responsible for tens of thousands
of deaths from lung cancer each year

10. Radon

11. Common Pollutants
Molds and Other Allergens
• These biological chemicals can arise from a host of
means, but there are two common classes:
• (a) moisture induced growth of mold colonies and (b)
natural substances released into the air such as animal
dander and plant pollen. In areas where cellulosic
materials (paper and wood, including drywall) become
moist and fail to dry within 48 hours, mold mildew can
propagate and release allergenic spores into the air.
• Mold is always associated with moisture, and its growth
can be inhibited by keeping humidity levels below 50%.

12. Molds and Other Allergens

13. Common Pollutants
Carbon Monoxide
• One of the most acutely toxic indoor air contaminants is
carbon monoxide (CO), a colorless, odorless gas that is a
byproduct of incomplete combustion of fossil fuels.
Common sources of carbon monoxide are tobacco
smoke, space heaters using fossil fuels, defective central
heating furnaces and automobile exhaust. Improvements
in indoor levels of CO are systematically improving from
increasing implementation of smoke-free laws. By
depriving the brain of oxygen, high levels of carbon
monoxide can lead to nausea, unconsciousness and
death.

14. Carbon Monoxide

15. Carbon Monoxide

16. Ozone
• Ozone is produced by ultraviolet light from the Sun
hitting the Earth's atmosphere (especially in the ozone
layer), lightning, certain high-voltage electric devices
(such as air ionizers), and as a by-product of other types
of pollution.
• Ozone exists in greater concentrations at altitudes
commonly flown by passenger jets. Reactions between
ozone and onboard substances, including skin oils and
cosmetics, can produce toxic chemicals as by-products.
Ozone itself is also irritating to lung tissue and harmful
to human health.

17. Ozone

18. The Causes
• Inadequate ventilation and air tightness
• Variations in temperature and humidity levels
• Indoor sources including combustion
• Infiltration of outdoor air contaminants
• Use of cleaning chemicals and building
products

19. The Causes

20. Indoor Pollutants
• Building Materials – Heavy
Metals, VOCs, Radon, Mineral Fibers etc
• Paints – Heavy Metals Electronic Equipments
• Respirable Organic Particulates, Ozone and
VOCs.
• Carpets - VOC’S
• Cleaning compounds/Cosmetics/Deodorants
• : Organics and VOCs
• Combustion Sources
• - RSPM, NO x, SO 2 , CO

21. Indoor Pollutants

22. Health Effects

23. Health Effects

24. Health Effects
• Symptoms related to poor IAQ are varied
depending on the type of contaminant. They
can easily be mistaken for symptoms of other
illnesses such as allergies, stress, colds, and
influenza. The usual clue is that people feel ill
while inside the building, and the symptoms go
away shortly after leaving the building, or when
away from the building for a period of time
(such as on weekends or a vacation).

25. Sick Building Syndrome
• 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 1984 World Health Organization
report suggested up to 30% of new and
remodeled buildings worldwide may be subject
of complaints related to poor indoor air quality.

26. Sick Building Syndrome

27. Sick Building Syndrome
• 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).

28. Sick Building Syndrome

29. Health Effects
• Effects from indoor air pollutants may be
experienced soon after exposure or, possibly, years
later. Symptoms may include irritation of the
eyes, nose, and throat; headaches; dizziness;
rashes; and muscle pain and fatigue.
• Diseases linked to poor IAQ include asthma and
hypersensitivity pneumonitis. The specific
pollutant, the concentration of exposure, and the
frequency and duration of exposure are all
important factors in the type and severity of health
effects resulting from poor IAQ.

30. Health Effects

31. Health Effects
• Age and preexisting medical conditions such as
asthma and allergies may also influence the
severity of the effects. Long-term effects due to
indoor air pollutants may include respiratory
diseases, heart disease, and cancer, all of which
can be severely debilitating or fatal

32. Health Effects

33. Health Effects
• Research has linked building dampness with significant health
effects. Numerous species of bacteria and fungi, in particular
filamentous fungi (mold), can contribute significantly to indoor
air pollution. Whenever sufficient moisture is present within
workplaces, these microbes can grow and affect the health of
workers in several ways.
• Workers may develop respiratory symptoms, allergies, or
asthma. Asthma, cough, wheezing, shortness of breath, sinus
congestion, sneezing, nasal congestion, and sinusitis have all
been associated with indoor dampness in numerous studies.
Asthma is both caused by and worsened by dampness in
buildings.

34. Sources of Indoor
Air Pollutants
Sources of indoor air pollution may include:
Building Site or Location
• The location of a building can have implications
for indoor pollutants.
• Highways or busy thoroughfares may be sources of
particulates and other pollutants in nearby
buildings. Buildings sited on land where there was
prior industrial use or where there is a high water
table may result in leaching of water or chemical
pollutants into the building.

35. Building Site or Location

36. Sources of Indoor
Air Pollutants
Building Design
• Design and construction flaws may contribute to indoor
air pollution. Poor foundations, roofs, facades, and
window and door openings may allow pollutant or water
intrusion. Outside air intakes placed near sources where
pollutants are drawn back into the building (e.g,idling
vehicles, products of combustion, waste containers, etc.)
or where building exhaust reenters into the building can
be a constant source of pollutants. Buildings with
multiple tenants may need an evaluation to ensure
emissions from one tenant do not adversely affect
another tenant.

37. Building Design

38. Sources of Indoor
Air Pollutants
Building Systems Design and Maintenance:
• When the HVAC system is not functioning
properly for any reason, the building is often
placed under negative pressure. In such
cases, there may be infiltration of outdoor
pollutants such as particulates, vehicle
exhaust, humid air, parking garage
contaminants, etc.

39. Building Systems Design and
Maintenance

40. Renovation Activities
• When painting and other renovations are being
conducted, dust or other by-products of the
construction materials are sources of pollutants
that may circulate through a building. Isolation
by barriers and increased ventilation to dilute
and remove the contaminants are
recommended.

41. Renovation Activities

42. Local Exhaust Ventilation
Kitchens, laboratories, maintenance
shops, parking garages, trash rooms, soiled
laundry rooms, locker rooms, copy rooms and
other specialized areas may be a source of
pollutants when they lack adequate local
exhaust ventilation

43. Building Materials
• Disturbing thermal insulation or sprayed-on
acoustical material, or the presence of wet or
damp structural surfaces (e.g., walls, ceilings)
• or non-structural surfaces (e.g., carpets, shades),
may contribute to indoor air pollution.

44. Building Materials

45. Building Maintenance
• Workers in areas in which pesticides, cleaning
products, or personal-care products are being
applied may be exposed to pollutants. Allowing
cleaned carpets to dry without active ventilation
may promote microbial growth.
Occupant Activities:
• Building occupants may be the source of
indoor air pollutants.

46. Building Maintenance

47. Common Pollutant
Categories
• Although there are numerous indoor air pollutants
that can be spread through a building, they typically
fall into three basic categories: biological, chemical,
Biological
• Excessive concentrations of
bacteria, viruses, fungi, dust mites, animal
dander, and pollen may result from inadequate
maintenance and housekeeping, water
spills, inadequate humidity
control, condensation, or water intrusion through
leaks in the building envelope or flooding

48. Biological Pollutants

49. Common Pollutant
Categories
Chemical
• Sources of chemical pollutants (gases and vapors)
include emissions from products used in the
building (e.g., office equipment; furniture, wall and
floor coverings; pesticides; and cleaning and
consumer products), accidental spills of
chemicals, products used during construction
activities such as adhesives and paints, and gases
such as carbon monoxide, formaldehyde, and
nitrogen dioxide, which are products of
combustion

50. Chemical Pollutants

51. Common Pollutant
Categories
Particle (Non-biological)
• Particles are solid or liquid, non-
biological, substances that are light enough to be
suspended in the air.
• Dust, dirt, or other substances may be drawn into
the building from outside. Particles can also be
produced by activities that occur in buildings such
as construction, sanding wood or
drywall, printing, copying, and operating
equipment.

52. Common Pollutant
Categories

53. IAQ Management
• It is recommended that building owners/managers
develop and implement an IAQ management plan
to address, prevent, and resolve IAQ problems in
their specific buildings. The EPA’s report,
• IAQ Tools for Office Buildings , provides a set of
flexible and specific activities that can be useful to
building owners/managers for developing such a
plan. IAQ policies, assessing the current status of
IAQ in buildings through periodic
inspections, maintaining appropriate logs and
checklists, performing necessary repairs and
upgrades, and implementing follow-up assessments
or other needed actions.

54. IAQ Management

55. IAQ Management
• An important management strategy is to foster a
team approach for problem solving and
consensus building. The IAQ Team should
include, but not necessarily be limited
to, building occupants, administrative
staff, facility operators, custodians, building
healthcare staff, contract service providers, and
other interested parties

56. IAQ Management

57. Identification and Assessment
• Methods used in an IAQ investigation may
include identifying pollutant sources, evaluating
the HVAC system performance, observing
production processes and work
practices, measuring contamination levels and
employee exposures, providing medical testing
or physical examinations, conducting employee
interviews, and reviewing records of medical
tests, job histories, and injuries and illnesses.

58. Identification and Assessment

59. Control Methods
• There are three basic control methods for lowering
concentrations of indoor air pollutants
• Source Management
• Source management includes removal, substitution, and
enclosure of sources. It is the most effective control method
when it can be applied practically.
• For example, the U.S. Consumer Product Safety Commission
recommends installing carpets that are low-volatile organic
compound (VOC) emitters, and encourages consumers to ask
retailers or installers about the carpet industry’s voluntary
“green label” program for new carpets. According to the carpet
industry, the green and white logo displayed on carpet samples
informs the consumer that the specific manufacturer’s product
has been tested by an independent laboratory and has met the
criteria for very low emissions

60. Source Management

61. Engineering controls
Local Exhaust
• Local exhaust, such as a canopy hood, is very effective in
removing point sources of pollutants before they can be
dispersed into the building’s indoor air.
General Dilution Ventilation
• General dilution ventilation systems, when properly
designed, operated, and maintained, will control normal
amounts of air pollutants. A well designed and functioning
HVAC system controls temperature and relative humidity
levels to provide thermal comfort, distributes adequate
amounts of outdoor air to meet the ventilation needs of
building occupants, and also dilutes and removes odors and
other contaminants.

62. Engineering Controls

63. Air Cleaning
• Air cleaning primarily involves the removal of
particles from the air as the air passes through the
HVAC equipment.
• Most HVAC system filtration is provided to keep
dirt off of coil surfaces to promote heat transfer
efficiency.
• Most smudging observed around air supply
diffusers in a ceiling result from entrainment
(trapping) of dirt particles in the space that
accumulate there because of poor housekeeping

64. Air Cleaning

65. Administrative Controls
Work Schedule
• Through scheduling, managers can significantly reduce the
amount of pollutant exposure in their buildings.
• For instance:
• 1. Eliminate or reduce the amount of time a worker is
exposed to a pollutant (i.e., scheduling maintenance or
cleaning work to be accomplished when other building
occupants are not present).
• 2.Reduce the amount of chemicals being used by or near
workers (i.e., limit the amount of chemicals being used by the
worker during maintenance or cleaning activities).
• 3. Control the location of chemical use (i.e., perform
maintenance work on moveable equipment in a maintenance
shop as opposed to the general area, or locate the equipment
(e.g., printers, copiers) in a separate room)

66. Administrative Controls

67. Administrative Controls
b. Education
• Education of building occupants regarding IAQ is
important. If occupants are provided with information
about the sources and effects of pollutants under their
control, and about the proper operation of the
ventilation system, they can alert their employer and/or
take action to reduce their personal exposure.
c. Housekeeping
• Housekeeping practices should include preventing dirt
from entering the environment (using, for example,
walk-off mat systems), removing dirt once it is in the
building, disposing of garbage,

68. Education

69. Housekeeping

70. Seeking Professional Assistance
• Some indoor air problems can be resolved when good
practices are put in place to control contaminants and
building personnel follow good housekeeping
approaches. Other problems may be difficult to
resolve, however, and may require outside assistance.

71. Seeking Professional Assistance
Examples of experts include:
Structural engineers - address issues with structural elements
such as corrosion problems in a building’s foundation;
Architects - responsible for designing the building envelope and
can mitigate water intrusion problems by designing vapor
barriers;
Mechanical engineers - test and balance HVAC systems and
may be able to assess and recommend repairs/replacement
of HVAC systems and local exhaust ventilation systems; and
Industrial hygienists - assess general IAQ parameters such as air
changes in a building, carbon dioxide levels, carbon
monoxide levels, and other indoor pollutants, and also
evaluate contaminant levels

72. Seeking Professional Assistance

73. Applicable Standards and Regulations
OSHA Standards
• All OSHA regulations, interpretations, and the OSH Act can be
found on www.osha.gov. Important OSHA statues and standards
include:
• Occupational Safety and Health Act of 1970
• Section 5(a)(1),
• often referred to as the General Duty Clause, requires employers to
“furnish to each of his employees employment and a place of
employment which are free from recognized hazards that are causing
or are likely to cause death or serious physical harm to his
employees.”
• Section 5(a)(2)
• requires employers to “comply with occupational safety and health
standards promulgated under this Act.”

74. Applicable Standards and Regulations

75. Applicable Standards and Regulations
• Some of the applicable OSHA Standards are:
• 29 CFR 1904, Recording and Reporting Occupational
Injuries and Illnesses.
• • 29 CFR 1910.94, Ventilation.
• • 29 CFR 1910.1000, Air Contaminants.
• • 29 CFR 1910.1048, Formaldehyde.
• • 29 CFR 1910.1450, Occupational exposure to
hazardous chemicals in laboratories.

76. Applicable Standards and Regulations
WHO Guidelines
• Concentration based -
PM10, PM2.5, CO, NO2, SO2, O3,
• Asbestos, Formaldehyde (Reference: WHO, 2006)
• New WHO guidelines are formed on the basis of
exposure levels, which gives an objective measure
of health risk and is used as reference point for
design and maintenance of safe indoor
environments -
Benzene, CO, Formaldehyde, Naphthalene, NO2
, PAH, Radon, Ethylene, dampness and Moulds
(Reference: WHO, 2010)

77. Applicable Standards and Regulations

78. AQ: Indian Context
• A standard IAQ Protocol is under process of development
The protocol is a check list for establishing a IAQ study in
India that includes sampling, monitoring, and analysis and
prediction of IAQ similar to NAAQM programme
• The Protocol Team
• IIT Delhi
• : Prof. Mukesh Khare
• NEERI
• : Dr. Anjali Shrivastava, Dr. Radha Goyal, Dr. S.K. Goyal
• CPCB
• : Dr. D. Saha
• Delhi University
• : Dr. Priyanka Kulshrestha

79. AQ: Indian Context

80. Fan Death
An Urban Legend
• Fan death is death supposedly caused by sleeping
in a closed room containing a running electric fan
Origins of belief
• The genesis of the misconception is unclear, but
fears about electric fans date almost to their
introduction to Korea, with stories dating to the
1920s and 1930s warning of the risks of
nausea, asphyxiation, and facial paralysis from this
"new technology”

81. Fan Death
An Urban Legend

82. Fan Death
An Urban Legend
Proposed causes
• Hypothermia
• Is abnormally low body temperature caused by
inadequate thermoregulation.
• As the metabolism slows down at night, one
becomes more sensitive to temperature, and thus
supposedly more prone to hypothermia. People
who believe this theory think a fan operating in a
closed room all night can lower temperature to the
point of causing hypothermia

83. Hypothermia

84. Fan Death
An Urban Legend
Asphyxiation
• It is alleged that fans may cause asphyxiation by
oxygen displacement and carbon dioxide
intoxication. In the process of human
respiration, inhaled fresh air is exhaled with a
lower concentration of oxygen gas (O2) and higher
concentration of carbon dioxide gas (CO2), causing
a gradual reduction of O2 and build-up of CO2 in a
completely unventilated room.

85. Asphyxiation

86. Fan Death
An Urban Legend
• Other indoor sources of carbon dioxide include
burning fossil fuels, such as a gas-fuelled water
heater, and seepage through foundations in areas
of high CO2 soil content. Carbon dioxide is a
colourless, odourless gas, and because it weighs
1.5 times more than normal air, it tends to
concentrate toward the floor, depending on
temperature and air currents. In South
Korea, some people sleep on traditional floor mats
called yos, while others prefer Western-style
beds, and floor vents may be absent in rooms
equipped with radiant underfloor
heating, called ondol

87. Fan Death
An Urban Legend

88. Fan Death
An Urban Legend
Actual hazard
• The American Environmental Protection
Agency (EPA) does not warn of fan death, but
discourages people from using fans in closed
rooms without ventilation during excessive heat,
specifically when the heat index is above 99 °F
(37 °C). The EPA does, however, approve of
using a fan if a window is open and it's cooler
outside, such as during overnight conditions, or
when the heat index in a closed room is below
90 °F (32 °C).

89. Fan Death
An Urban Legend

90. Fan Death
An Urban Legend
Professional Opinion
• Dr. John Linton, of Yonsei University's Severance
Hospital, who is licensed to practice medicine in South
Korea, has said:
There are several things that could be
causing the fan deaths, things like pulmonary
embolisms, cerebrovascular accidents or arrhythmia.
There is little scientific evidence to support that a fan
alone can kill you if you are using it in a sealed room.
Although it is a common belief among Koreans, there
are other explainable reasons for why these deaths are
happening

91. Fan Death
An Urban Legend

92. Fan Death
An Urban Legend
• Dr. Lee Yoon-song is a professor at Seoul National
University's medical school and works with the school's
Institute of Scientific Investigation. He has conducted
autopsies on some of the people who have been
described in Korean media as having succumbed to fan
death, and said:
• “When someone's body temperature drops below 35
degrees, they do start to lose judgment ability. So if
someone was hiking and later found dead, that could be
part of the reason. But we can't really apply this to fan
accidents. I found most of the victims already had some
sort of disease like heart problems or serious alcoholism.
So hypothermia is not the main reason for death, but it
may contribute”.

93. Fan Death
An Urban Legend

94. References
Environmental Management
Bala Krishnamoorthy- PHI publication
Wikipedia- The online free Encyclopedia
https://www.osha.gov/
http://www.igbc.in/

95. Think Global Act Local
Thanks …