Introduction Although pollutant concentrations vary significantly from building to building, the levels of some common air pollutants often are greater indoors than outdoors. Since most people spend more time indoors than outdoors, exposure to indoor air pollutants is an important environmental problem.
To be cont……….. Air pollution is the introduction of chemicals, particulate matter, or biological material that cause harm discomfort to humans or other living organisms, or damages the natural environment, into the atmosphere.
What’s indoor air pollution? Indoor Air Pollution is the term used to describe the amount of contaminants in the air inside a building from sources such as cigarette smoking, fuel combustion for heating or cooking, certain wallboards, carpets, or insulation as well as the geology of the area (radon in soil or rocks beneath the structure).
To be cont……….. Refers to good and bad effects of the contents of air inside a structure on its occupants Good indoor air quality(IAQ) has no unwanted gases or particles in it at concentrations which will adversely affect someone Poor indoor air quality has gases or particles in excessive concentration so as to affect the satisfaction or health of occupants
What Causes Indoor AirPollution?? Air tightness of buildings Poorly designed air conditioning and ventilation systems Indoor sources of pollution Outdoor sources of pollution
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 odor (Bioaerosols) and other pollutants. Pull outside polluted air from vents, cracks and openings and increase dust, pollen etc. Causes “Sick Building Syndrome”.
Sources of Indoor Air Pollutionin a Typical Office Building
Sources of Indoor Air Pollution in a TypicalHousehold
Poorly Designed AirConditioning Systems Results into the production of fungi, molds and other sickness causing microbes.
What is IAQ?? IAQ stands for “Indoor Air Quality”. It refers to the nature of the conditioned (heat/ cool) air that circulates throughout space/area, where we work and live i.e. the air we breathe most of the time (almost 80 % of the time).
Problems of IAQEnclosed spaces inhabited by humans producefollowing effects- Reduction in oxygen level of spaces. Increase in CO2 level. Increase in temperature. Increase in humidity Increase in Bioaerosols and odor
Relationship between Indoor and OutdoorAir QualityIndoor Air Quality Outdoor Air Quality Indoor pollutant Outdoor contaminants concentrations may be may be present higher or lower than indoors at a sufficient outdoor air concentration to affect concentrations the occupantsExample : Pollen and mold spores from outdoors causes hay fever and allergies indoors
Why should you be concerned about thequality of air that you breath? The contaminant indoor air could damage people’s health Indoor air pollutants are among the top five environmental risk People spend about 90% of their time indoors and so the health problems that result from exposure to indoor pollution increases According to World Health Organization (WHO) approximately 30% of all commercial buildings have significant IAQ problems
Sources of Pollutants Normal Biological Processes - people and pets generate carbon dioxide, moisture, odors and microbes Combustion appliances such as wood stoves, gas stoves, furnaces, fireplaces and gas heaters Use of consumer products such as spray cans, air fresheners, spray cleaners and construction materials Cigarette smoking Soil under and around buildings Appliances such as humidifiers, air conditioners and nebulizers
Sources involved in IAQ problems Evaluations by National Institute for Occupational Safety and Health (NIOSH) for studies on more than 500 Indoor Air quality health hazard cases Bioaerosols 5% Inside contamination 15% Outside Contamination Inadequate 10% Ventilation Building 53% products 4% Unknown causes 13%
Percent Typical SourcesProblem Origin Lack of outside air, poor air distribution, uncomfortableInadequate Building 53% temperature and humidity,Ventilation Systems contaminant sources inside the system Solvent vapors, dusts,Contaminants Originating 15% formaldehyde, building materials,Inside Building furnishingsBuilding Products 4% Concrete, wood, furnishings.Unknown Causes 13% Unidentified sourcesOutdoor Contaminants Motor vehicle exhaust, pollen, 10%Entering Building fungi, smoke, constructionMicrobiological Agents 5% Bioaerosols, Legionella
How does Outdoor Air enterIndoors Infiltration - outdoor air flows into the house through openings, joints, and cracks in walls, floors, and ceilings, and around windows and doors Natural Ventilation - air moves through opened windows and doors Mechanical Ventilation - from outdoor-vented fans that intermittently remove air from a single room, such as bathrooms and kitchen, to air handling systems that use fans and duct work to continuously remove indoor air and distribute filtered and conditioned outdoor air to strategic points throughout the house
Health effects due to IndoorAir Pollutants Headaches Nausea Respiratory infections Asthma Hypersensitivity pneumonitis Humidifier fever Legionnaire’s disease Lung cancer
Health Symptoms and Possible Contaminants SYMPTOM POSSIBLE PRIMARY ENVIRONMENTAL CONTAMINANTS SOURCES CONDITION· Headache · Bio-aerosols · Ventilation systems · Ergonomic· Fatigue · VOCs · Humidifiers Conditions· Poor Concentration · Drip pans · Noise and· Dizziness · Cooling coils in AHVs Vibration· Tiredness · Plants · Outside air· Headache with nausea · CO · Incomplete · Ergonomic· Ringing in ears · Formaldehyde Combustion (vehicle Conditions· Pounding heart Exhaust, stoves, · Noise and fireplaces) Vibration · Building products · Furnishings· Dry Throat · NO2 · Incomplete · Relative· Shortness of breath · Formaldehyde Combustion humidity or Bronchial Asthma · VOCs · Building Products· Irritation and · Particulates · Furnishings Infection of · Smoking Respiratory Tract
To be cont…………….. SYMPTOM POSSIBLE PRIMARY ENVIRONMENTAL CONTAMINANTS SOURCES CONDITION· Nasal Problems · NO2 · Incomplete Combustion · Relative Humidity (Stuffiness,Irritation) · Formaldehyde · Building Products · High Temperatures · Bio-aerosols · Furnishings · Ventilation Systems · Humidifiers · Drip Pans · Cooling Coils in AHVs · Outside Air· Skin Problems · Formaldehyde · Ventilation Systems · Warm Air (Dryness, Irritation, · Humidifiers · Low Relative Rashes) · Outside Air Humidity · Excessive Air Movement· Eye Problems · NO2 · Incomplete Combustion · Artificial Light (Burning, Dry Gritty · Formaldehyde · Building Products Eye) · VOCs · Furnishings · Particulates · Ventilation Systems · Bio-aerosols · Humidifiers · Cooling Coils in AHVs · Outside Air · Building Product Deterioration
List of Pollutants affectingIAQ Volatile organic compounds (VOCs) Dust and dirt Radon Environmental tobacco smoke (ETS) Respirable Particulate Matter (RPM) Carbon and Nitrous Oxides
Indoor Air Pollutants and Their Health Effects Pollutant Effects LimitsNO2 Type: Immediate 0.05 ppm (avg. over one year for 8 hours exposure daily)- EPA Causes: irritation to the skin, eyes and throat, cough etc.CO Type: Immediate 9.0 ppm (avg. over 8 hours Causes: headache, shortness of breath, higher conc. May cause sudden period)- EPA deaths.RSPM Type: Cumulative 150 µg/ m3 (24 hr. average) Causes: Lung cancerSO2 Type: Immediate 0.05 ppm (avg. over one year for 8 Causes: lung disorders and shortness of breath hours exposure daily)- EPARadon Type: Cumulative >/ 4 pCi/ Litre of indoor air Causes: Lung cancerFormaldehyde Type: Immediate 120 g/ cu.m. (continuous exposure)- ASHRAE Causes: irritation to the eyes, nose and throat, fatigue, headache, skin allergies, vomiting etc.Asbestos Type: Cumulative >/ 2 fibers/ cu.cm. Of the indoor Causes: Lung cancer air (8 hrs. exposure period)- OSHAPesticides Type: Immediate - Causes: Skin diseasesVOCs Type: Immediate Not for all VOCs. Causes: Liver, kidney disorders, irritation to the eyes, nose and throat, skin For chlordane: rashes and respiratory problems. 5 g/cu.m.(continuous exposure))CO2 Surrogate index of ventilation 1000 ppmO3 Type: Immediate 100 g/cu.m (continuous exposure)- OSHA Causes: eyes itch, burn, respiratory disorders, lowers our resistance to colds and pneumonia.