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Refrigeration and air conditioning.
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Historical Perspective First indication of indoor contamination –
Asbestos pollution, a carcinogenic substance, discovered by epidemiologists, used in almost all building materials about 35 years back. Banned due to adverse health effects NOT considering IAQ.
Concept of IAQ first introduced among scientific community in 1980 due to some occurrences of ‘episodes indoors’.
At central headquarters of EPA building at Washington, D.C.- more than 100 people fell sick within 15 minutes of entering the office.
In Los Angeles, CO level in most of the well insulated buildings was three times greater than the outside level.
Outcome: Such episodes indoors in developed nations ended up with Extensive monitoring programme for indoors Identification of indoor contaminants Formulation of IAQ models Development of control methodologies Formulation of Indoor Air Contamination
Standards. Identification of ‘Sick Buildings’ Investigation of ‘Sick Building Syndrome
(SBS)’
Hard FactsFresh air contains 21.0% (v/v) O2 and
Exhaled air contains 17.0% (v/v) O2
An adult emits 45 gm sweat / hour containing bioaerosols.
An adult produces about 80 to 100 W heat.
Carbon based gaseous pollutants (VOCs) in indoors are 2 to 5 times higher than outdoors.
Indoor Air Quality (IAQ)
Characteristics of Indoor Air QualityPhysicalChemical Biological
FactorsCause IAQ IssuesImprove IAQ
What is IAQ?
Office Type Environment Ventilation is General Dilution
Type Heating, Ventilating, and Air
Conditioning (HVAC) System Windows
Truth!!!!
What is more agreeable than one’s home?
Feeling safe ?Away from outside pollution ?
Air inside the conditioned space can be substantially more polluted than outdoor air.
Energy Efficiency Starting in the 1970’s Buildings
were Sealed Up to Reduce Energy CostsAir Contaminants TrappedLack of Outdoor AirSick Building Syndrome
American Society of Heating, Refrigeration & Air-Conditioning Engineers (ASHRAE) Standard 62 – Recommends 7 to 10 L/s (CFM) of Outdoor Air per Person
Causes of IAQ Problems Temperature and/or Humidity Too Much Glare Inadequate Fresh Air - Lead to
Carbon Dioxide (CO2) BuildupNormal Outdoor CO2 Levels is 350
ppmIndoor CO2 Levels Can Be 600-800
ppm> 1000 ppm CO2 Levels –
Tired/SleepinessOSHA Permissible Exposure Limit for
CO2 is 500 ppm
CO2
Introduction of Chemicals & Contaminants into the Building
Building Remodeling - Adhesives, Paints Select Low Volatile/Low Toxicity Products Schedule Work on Weekends/After Hours Allow Remodeled Area to Off-Gas Prior to
Re-Occupation Temporarily Relocate Employees
Old Food - Forgotten Lunches/Snacks
Introduction of Chemicals & Contaminants into the Building Cleaners
Use Green Seal Cleaning Supplies Non-Toxic Not a Skin Sensitizer Does Not Contain Substances Which
Contribute to Poor Indoor Air Quality If Using a Cleaner - Be Aware of How
Your Actions May Impact Your Co-Workers
Building Air Inlet - Auto Exhaust can increase Carbon Monoxide
Introduction of Chemicals & Contaminants into the Building
Personal Hygiene Products Perfumes, Deodorants, Cologne
Be Aware of How Your Actions Can Impact Your Co-Workers
Water Leaks/Water Damage Mold or Mildew
Air Cleaners - Some Use Ozone May Affect Persons with Pre-Existing
Respiratory Problems
Introduction of Chemicals & Contaminants into the Building
Printers/Copying MachinesCan Generate Particulates and OzoneOzone – Eye & Respiratory IrritationDo Not Place in Room with Poor
VentilationDo Not Point Printer Exhaust at
IndividualsStudy on Printers:
Ozone Levels: <0.001 ppm to 0.016 ppm (OSHA permissible exposure limit for ozone. 0.1 ppm)
Introduction of Chemicals & Contaminants into the Building
Animal DanderBrought into the Office on ClothingSome Persons have Allergic
Reactions Third Hand Smoke
Recent Studies – Tobacco By-Products Can Cling to Hair, Clothing, & Furniture
Be Sensitive to the Needs of Co-Workers
Monitoring for IAQ Issues Q-Trak Indoor Air Quality
MonitorTemperature and HumidityCarbon MonoxideCarbon Dioxide
ppb RAE DetectorVarious Chemical
Substances Down to the Parts per Billion Rang
Monitoring for IAQ Issues
Chemical HazardsDo Not Use Odor as an Indicator of
HazardCertain Individuals May Be More
Susceptible to Certain ChemicalsAll Chemicals Do Not Have a
Permissible Exposure Limit
In Summary Certain Individuals May Be More
Susceptible to Certain Chemicals Be a Good Neighbor/Co-Worker Don’t Be Afraid to Ask & Do Not Be
Offended If a Co-Worker Asks Discuss IAQ Issues With Your
Supervisor, Department Safety
Officer.