Indoor Air Quality (IAQ) is a critical component of environmental health and occupational safety. People spend a significant portion of their time indoors—at home, in offices, or public buildings—and the quality of air in these environments directly affects their health, productivity, and well-being. This unit covers the sources and types of indoor air pollutants, control strategies, sick building syndrome, radon pollution, and also addresses noise pollution—its sources, effects, measurement, and control. Sources and Types of Indoor Air Pollutants Indoor air pollution arises from numerous sources, both natural and human-made. Common indoor air pollutants include: Biological contaminants: Mold, bacteria, viruses, pet dander, pollen, and dust mites. Chemical pollutants: Volatile Organic Compounds (VOCs) from paints, cleaning products, adhesives, and furnishings. Combustion products: Carbon monoxide (CO), nitrogen dioxide (NO₂), and particulate matter from stoves, heaters, and fireplaces. Building materials: Formaldehyde from pressed wood products, asbestos from insulation, and lead from old paints. Tobacco smoke: Contains numerous harmful chemicals and is a major indoor pollutant. Radon gas: A radioactive gas naturally released from the ground into buildings, especially in poorly ventilated basements. Control of Indoor Air Pollutants Effective control strategies include: Source control: Eliminating or substituting polluting materials and products. Ventilation: Introducing fresh outdoor air through mechanical or natural means to dilute indoor pollutants. Air cleaning devices: Use of filters, air purifiers, and electrostatic precipitators to remove airborne contaminants. Humidity control: Maintaining relative humidity between 30–50% to minimize mold and dust mites. Building design: Using non-toxic materials and proper HVAC systems in green building practices. Sick Building Syndrome (SBS) Sick Building Syndrome refers to 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. Symptoms include: Headaches, eye, nose, or throat irritation Fatigue, dizziness, and nausea Difficulty concentrating Allergic reactions Types of SBS: Chemical-based: Due to VOCs, cleaning agents, and synthetic materials. Biological-based: Resulting from mold, bacteria, or fungi. Ventilation-based: Due to poor air exchange or HVAC malfunctions. Radon Pollution and Its Control Radon is a colorless, odorless, radioactive gas produced by the decay of uranium in soil and rock. It can seep into buildings through cracks in floors and walls and is a leading cause of lung cancer after smoking. Control measures include: Sealing foundation cracks and joints Installing radon venting systems Improving ventilation, especially in basements Noise Pollution: Sources and Effects Sources: Traffic, industrial operations, construction, dome

1. UNIT V INDOOR AIR QUALITY MANAGEMENT
Sources, types and control of indoor air pollutants, sick building
syndrome types – Radon pollution and its control – Sources and
Effects of Noise Pollution – Measurement – Standards – Control
and Preventive measures.

2. Indoor air pollution
• Indoor air pollution is dust, dirt, or gases in the air inside buildings
such as your home or workplace that could be harmful to breathe
in.
• Poor indoor air quality has been linked to lung diseases like asthma,
COPD and lung cancer. It has also been linked to increased risk of
heart disease and stroke.

4. Common indoor air pollutants include
• Tabacco smoke
• Biological pollutants
• Radon
• Carbon monoxide

5. • Indoor Air Pollutants is the term used to describe the physical,
chemical and biological characteristics and the amount of the
contaminants in the air inside a building from sources such as cigarette
smoking, fuel consumption for heating or cooking.
• Volatile organic compounds
• Tobacco smoke
• Pesticides
• Biological pollutants
• Formaldehyde
• Asbestos
• Radon

6. Important Indoor Air Pollutants
Indoor air pollutants Sources
Nitrogen dioxide Building materials
Carbon monoxide Furnishing and fabrics
Volatile organic compounds (VOCs) Combustion appliances (cooking & heating)
House dust mite (& other allergens from pets) Living organisms
Chlorinated organic compounds Cleaning products
Asbestos & man-made fibers Openfires, smoking

7. Air Tightness in Buildings
• Causes inadequate supply of fresh air, as a result, negative pressure
develops which causes
• Ground level pollutants, e.g. CO, Radon etc., to be drawn inside the buildings.
• Release of odour (Bio aerosols) and other pollutants
• Pull outside polluted air from vents, cracks and openings and increase dust,
pollen etc.,
• Causes “Sick Building Syndrome”.

8. Sources of Indoor air pollutants
• Radon (Rn)
• Secondhand Smoke/ Environmental Tobacco Smoke
• Biological Sources
• Carbon Monoxide (CO)
• Nitrogen Dioxide (NO2)
• Organic gases
• Respirable particles
• Formaldehyde/ Pressed wood products
• Pesticides
• Asbestos

38. Sources and Effects of Noise Pollution
Sound
• Sound is a vibration that propagates as a mechanical wave of pressure
and displacement, through some medium (i.e. air or water).
• Sound refers to only those vibrations with frequencies that are within
the range of hearing for human.

39. Noise
• Noise pollution is considered to be any unwanted or disturbing
sound that affects the health and well-being of humans and other
organisms. Sound is measured in decibels.
• It is measures in dB units.

40. Characteristics of Noise
• Sound pressure
• Frequency
• Duration
• Time of the day
• Location
• Intermittency

41. Kinds of Noise
• Continuous
• Variable or Intermittent
• Impulse or Impact
Kinds of noise which affect analysis
• Chemical Noise
• Instrumental Noise

43. Noise Pollution
• Noise pollution refers to a type of energy pollution in which
distracting irritating or damaging sounds freely audible.

44. Sources of Noise Pollution
• Household Sources
• Social Events
• Commercial and Industrial Activities
• Transportation

45. Household Sources
• Food mixer
• Grinder
• Vacuum Cleaner
• Washing machine and dryer
• Air conditioner
• Straighter and curlers
• Cooler
• TV
• iPods and Earphones
• Loud speaker
• Neighbor’s Barking Dog

47. Social Events
• Places and Worship
• Parties
• Markets where people sell goods with loudspeaker.
When these events are not often, they can be termed as nuisance
rather than noise pollution.

49. Commercial and Industrial Activities
• Printing presses
• Manufacturing Industries
• Construction Sites

50. Sources of Construction Noise
• Pneumatic Hammers
• Air compressors
• Bulldozers
• Loaders
• Dump Trucks
• Pavement breakers

52. Sources of Industry Noise
• Fans
• Motors
• Compressors mounted outside

54. Transportation
• Road Traffic Noise
• Aircraft Noise
• Noise from Rail Roads

56. Effects of Noise Pollution
• Effects on Human
• Effects on Animals
• Effects on Environment (Vegetation, Property)

57. Effects on humans
• Hearing impairment
• Interference with spoken communication
• Decrease in efficiency
• Lack of Concentration
• Fatigue
• Sleep disturbances
• Cardiovascular Disturbances

58. • Disturbance in mental health
• Impaired task performance
• Negative social behavior and annoyance reactions
• Temporary or permanent deafness
• Abortion
• Abnormal fetus

60. Effects on Animals
• Damages nervous system
• Creates problem in navigation
• They become dangerous and attacking
• Raise metabolism
• Reduction of useable habitat
• Death of certain species
• Genetic and Evolutionary Problems
• Injury
• Panic and escape behavior

61. Effects on Environment
• Breakage of Earth barrier
• Poor quality of Crops
• Damages building, bridges and monuments
• Weakens the edifice of building