Presentation is loading. Please wait.

Presentation is loading. Please wait.

Occupational Safety and Health Bureau

Similar presentations

Presentation on theme: "Occupational Safety and Health Bureau"— Presentation transcript:


2 Occupational Safety and Health Bureau
INDOOR AIR QUALITY JUDY MURPHY Industrial Hygienist Montana Department of Labor Occupational Safety and Health Bureau

3 Introducing…………… Please tell us Your name Where you work What you do
Your indoor air quality experience & concerns

4 Is IAQ Important? 30% of newly constructed or remodeled facilities have IAQ problems Indoor contaminants are responsible for half of all illnesses Liability issues

5 Liability Owners and managers Architects, builders and developers
Product manufacturers Insurers Unions Real estate agents, bankers and sellers

6 Why is There an Increase in IAQ problems?
More time indoors More chemical pollutants in buildings Tighter buildings and reduced ventilation Deferred maintenance

7 Common Health Effects of Indoor Contaminants
Eye, nose and throat irritation Coughing and sneezing Headaches Fatigue Irritability Allergies, sinus congestion Dizziness Difficulty in concentrating

8 Health Effects Depend on Several Factors
The contaminant The amount of the contaminant present The length of time a person is exposed to the contaminant The vulnerability of the person

9 Sick Building Syndrome
Symptoms include eye, nose and throat irritation, headache, allergies, fatigue 20% or more of occupants experience same symptoms No medically diagnosable symptoms Complaints persist for more than two weeks Symptoms often lessen after person leaves building

10 Building-Related Illness
Clinically defined illness or disease E.g. Asthma, Legionaires’ Disease, Hypersensitivity Pneumonitis Symptoms depend on the disease Hypersensitivity pneumonitis: allergic alveolitis; a pulmonary response to exposure to organic particles or gases; may also occur with exposure to isocyanates and cobalt. Classical acute episode starts with fever, muscular aches, and general malaise some 4 to 8 hours after exposure to the antigen. Occasionally, this is preceded or accompanied by wheeze or tightness in the chest and a dry cough. Shortness of breath is a feature of more severe attacks and may occasionally be dramatic and disabling or even fatal. Symptoms typically reach a peak at about 8 to 12 hours after exposure and then improve over another 12 to 24 hours in the absence of further exposure. Humidifier fever is an example of H.P.; usually worse on Monday morning if humidifier is at workplace.

11 QUIZ What are some of the most common IAQ health effects?
What four factors determine the health effects of an exposure to hazardous compounds?

12 Regulations and Standards
Outdoor airborne contaminant levels Environmental Protection Agency (EPA) National Ambient Air Quality Standards (NAAQS) Indoor airborne contaminant levels in the workplace Occupational Safety and Health Administration (OSHA) ASHRAE Standards , , ,

13 ASHRAE Ventilation Standards
ASHRAE – Objective of ventilation is satisfaction of 80% of inhabitants

14 OSHA Permissible Exposure Levels (PELs)
“Time-weighted average concentrations that must not be exceeded during any 8-hour workshift of a 40-hour workweek” Legally enforceable Measured in parts per million (ppm) or milligrams per cubic meter (mg/m3)

15 Threshold Limit Values (TLVs)
“Time-weighted average concentration for a conventional 8-hour workday and a 40-hour workweek, to which it is believed that nearly all workers can be repeatedly exposed, day after day, without adverse effect” Guidelines Generally more conservative than PELs

16 Problem - Causing Compounds
Chemicals Combustion products Respirable particles and gases Biological aerosols


18 Volatile Organic Compounds (VOCs)
Carbon-containing compounds that evaporate rapidly Examples Benzene Toluene Styrene Perchloroethylene Pesticides

19 Volatile Organic Compounds (Sources)
Paints, stains, varnishes Waxes Polishes Solvents Pesticides Adhesives Wood preservatives Cleansers Lubricants Air fresheners Fuels Plastics Copy machines, printers Tobacco products Perfumes Dry cleaned clothing

20 PESTICIDES - Symptoms Depression Impaired judgment Memory deficits
Visual disturbances ECG changes Weakness Fatigue Paralysis Headache Dizziness Lack of coordination Nervousness Irritability Insomnia Confusion Loss of concentration Speech difficulties

21 Integrated Pest Management
IPM Steps Set action thresholds Monitor and identify pests Prevention Control Action thresholds – point where pest control action must be taken Monitor & identify – not all pests are harmful; some are beneficial Prevention – e.g. crop rotation, pest-resistant varieties Control – mechanical controls, traps, habitat control, pheromones

22 Formaldehyde Used in plywood, paneling, particleboard, wallboard, fiberglass, adhesives Sometimes in ceiling tiles, wallpaper, furniture, draperies, clothing Even low levels can cause difficulties in breathing, burning of eyes nose and throat, coughing; a human carcinogen PEL 0.75 ppm; TLV ceiling limit 0.3 ppm

23 Perchloroethylene Solvent used in dry cleaning, metal cleaning and degreasing Can cause irritation of eyes, nose, throat and skin, liver and kidney damage, CNS depression Considered an animal carcinogen and probable human carcinogen PEL 100 ppm; TLV 25 ppm OSHA PEL: 100 ppm CEILING LIMIT: 200 ppm ACGIH TLV: 25 ppm SHORT TERM EXPOSURE LIMIT: 100 ppm

24 Perchloroethylene MSDS Exercise

25 QUIZ What are VOCs? What are some sources of VOCs
What are some alternatives to pesticides?


27 Combustion Products Carbon monoxide (CO) Oxides of nitrogen (NOx)
Oxides of sulfur (SOx) Carbon dioxide (CO2) Polycyclic Aromatic Hydrocarbons (PAH) Tobacco Smoke components

28 Carbon Monoxide (CO) Colorless, odorless, tasteless poisonous gas
Produced as a by-product of combustion Deprives the body of oxygen by binding to blood hemoglobin and displacing oxygen molecules

29 Carbon Monoxide Symptoms are headache, dizziness, drowsiness and nausea Severe exposure results in vomiting, collapse, coma and death PEL 50 ppm; TLV 25 ppm Body systems most affected are the brain, the heart, and the developing fetus

30 Carbon Monoxide Low levels of exposure - more frequent attacks of angina, reduced athletic performance, heart attacks Moderate exposures - loss of attentiveness, decreased visual perception, manual dexterity, learning ability and driving ability Smoking – cause of the greatest human exposure

31 Carbon Dioxide (CO2) Colorless, odorless, tasteless gas at room temperature Present in exhaled human breath Combustion by-product Naturally present in an unpolluted environment at about 300 ppm

32 Carbon Dioxide CO2 levels above 800 ppm may indicate inadequate ventilation ASHRAE recommended indoor air quality limit for CO2 is 1000 ppm PEL 5000 ppm; TLV 5000 ppm

33 Tobacco Smoke Respirable particles and gases, including benzene, carbon monoxide, formaldehyde, hydrogen cyanide, ammonia and VOCs Sidestream smoke from cigarette contains higher concentrations of some toxic and carcinogenic substances than mainstream smoke inhaled by smoker

34 Tobacco Smoke Causes lung cancer in nonsmokers as well as smokers
Increased respiratory infections in children Irritation of upper respiratory tract, coughing, wheezing, sneezing, headache, sinus problems, asthma, increased cardiovascular risk

35 QUIZ Which combustion by-products would you expect to see in smog?
Which compound is sometimes used as a measure of ventilation efficiency? Smog: CO, CO2, ozone, particulates, VOCs, NOx, SO2


37 Respirable Particles & Gases
Asbestos Fiberglass Silica Metal dust Tobacco smoke components Organic dust Pollen Mold spores Paper dust Radon

38 Asbestos Group of indestructable highly fibrous minerals
Separated fibers are long, thin, flexible, heat resistant, able to be spun and woven Health effects: lung cancer, mesothelioma, asbestosis, pleural plaques Airborne concentration in homes and schools 30 to 6,000 fibers/m3 PEL 0.1 fiber/cc; TLV 0.1 fiber/cc

39 Lead Indestructable, non-biodegradable, adaptable metal
Romans used lead to line aqueducts, as mortar, in plumbing and to sweeten wine Was used in gasoline, batteries, paints, ceramic glazes, ammunition, fishing sinkers, metal toys

40 Lead Three quarters of the nation’s housing contains lead-based paint
Children are at greater risk for lead poisoning than adults Hand to mouth activity Developing body systems more easily affected Action level is 10 micrograms per deciliter (μg/dl)

41 Lead – Chronic Exposure Health Effects
Loss of appetite Metallic taste in mouth Anxiety Constipation Nausea Palor Excessive tiredness Weakness Insomnia Headache Nervous irritability Muscle and joint pain or soreness Fine tremors Numbness Dizziness Hyperactivity Colic, with severe abdominal pain

42 Chronic Effects of Lead Poisoning in Children
Fetal development abnormalities Decreased intelligence Slowed neurological development Reading and learning problems Reduced attention span

43 Chronic Effects of Lead Poisoning in Children (cont.)
Hearing loss Behavioral problems such as hyperactivity Stunted growth Permanent damage to the brain, nervous system and kidneys

44 Sources of Potential Exposure to Lead
Lead-based paint Lead-contaminated dust Lead-contaminated soil Candle wicks Pewter and silver products Lead crystal Some lead-glazed pottery and porcelain Some imported mini-blinds

45 Radon Naturally occurring radioactive gas
Colorless, odorless, tasteless Causes no symptoms of irritation or discomfort No early signs of exposure Testing a building is the only way to evaluate exposure Action level is 4 picocuries per liter (pCi/L)

46 Radon Health Effects Damage by alpha radiation to tissue of lungs and respiratory tract 20,000 lung cancer deaths per year Non-smokers risk of lung cancer at 4 pCi/L is 2 in 1000 Smokers risk of lung cancer at 4 pCi/L is 20 in 1000

47 Testing for Radon Test in lowest livable area in building
Close all doors and windows 12 hours before testing Do not test in kitchen or bathroom Place monitor at least 20 inches above floor Test during coldest months of the year

48 Radon Control Measures
Increasing the ventilation in the building Sealing the foundation Sub-slab depressurization

49 Sub-Slab Depressurization

50 QUIZ What are some of the health effects of lead exposure?
How can you tell if a building has elevated radon levels?


52 Bioaerosols Substances that are living or were released from a living organism Examples Bacteria Fungi Pollen Viruses Dust mites

53 Dust Mites

54 Dust Mites Microscopic relatives of spiders
Feed on dead skin scales and other organic debris 2,000,000 in an average bed Dust mite feces - a common allergen Prefer relative humidity level above 55%

55 Viruses Smallest and simplest of all life forms
Depend completely on their hosts for reproduction Continually undergo evolutionary change Examples Influenza HIV Rhinovirus

56 Hanta Virus Carried in wild rodents, especially deer mice
Can cause respiratory failure and death Approximately 43 % of diagnosed cases have been fatal Infection is caused by inhalation of airborne particles of infected urine, droppings or saliva from infected animals

57 Hanta Virus Precautions
Seal any holes larger than a dime Air out unused buildings before entering Wear a NIOSH-approved mask when cleaning Spray surfaces with disinfectant, leave for 15 minutes, then sweep Wash hard surfaces with disinfectant

58 Bacteria Single-celled prokaryotic organisms
Most are very small spheres, rods or filaments Reproduce by simple cell division Some produce endospores, which are extremely resistant to harsh conditions A few require living hosts

59 Bacteria in Indoor Environments
Higher concentrations indoors than outdoors Majority of bacteria in air are shed from human skin and respiratory tracts Examples of infectious bacteria Legionella spp. Staphlococcus aureus Mycobacterium tuberculosis

60 Bacterial Toxins Exotoxins Endotoxins Excreted
Clostridium botulinum exotoxin - one of the most powerful poisons known Endotoxins Part of cell wall of gram negative bacteria Highly toxic – fever, malaise, changes in white blood cell counts, respiratory distress, shock, even death

61 Mold

62 Mold? Where??

63 Mold on ceiling and walls

64 Mold in a closet

65 Mold in air duct

66 Fungi as Food Mushrooms Soy sauce Yeast Bread Cheese Wine Beer

67 Mucor species Example of Zygomycetes: Mucor species showing sporangia, columella and sporangiospores; asexual stage

68 Penicillium species Ascomycetes example: Penicillium conidiospores; asexual stage

69 Aspergillus niger Ascomycetes example: conidia of Aspergillus niger
Most frequently associated agent of otomycosis. Third most common species associated with invasive pulmonary aspergillosis.

70 Aspergillus fumigatus
Example of Ascomycetes: conidial head of Aspergillus fumigatus Most common cause of invasive and non-invasive aspergillosis. Thermotolerant, grows at temperatures up to 55 degrees C. Has been found everywhere, on every conceivable substrate, especially soil and decaying organic matter.

71 Cryptococcus neoformans var. neoformans
Found in pigeon and bat droppings. Not usually infectious. May affect CNS, particularly in immunocompromised persons. Sept cases of cryptococcal disease in Vancouver, B.C. Four died. Symptoms: fever, chills, vomiting, headache, dizziness, chest pain, confusion, dementia

72 Growing Conditions Optimum water activity Optimum temperature range
Above 0.90 in substrate, for most species Optimum temperature range 56°F to 86°F, for most species Light Inhibits growth of some types of molds Stimulates spore production in many species Water activity – 0.90 is soaking wet; preferred by most species, not all Temp – 15 to 30 degrees C is 59 to 86 degrees F; preferred by most species, not all Light – dark areas are often also damp Some areas that meet these criteria: inside walls backing of sheetrock inner surface of wallpaper upper side of ceiling tiles under floor tiles or carpet inside ventilation systems areas of debris by air intakes humidifiers AC drip pans

73 Fungal Metabolism Enzymes secreted to digest external food sources, which are then absorbed Must have adequate moisture available

74 Metabolic Products Carbon dioxide, water, ethanol
Microbial Volatile Organic Compounds (MVOCs) Mycotoxins and antibiotics Primary metabolism Necessary for maintaining life e.g. extracting energy from nutrients, building and repairing cells e.g. aerobic respiration, digestion Secondary metabolism Gives the fungi or bacteria a competitive advantage over other organisms Iincludes mycotoxins, antibiotics, and some VOCs

75 MVOCs VOCs with distinctive offensive odors
Possibly responsible for some illnesses Different compounds emitted on different media Type and quantity change with phases of growth Highest MVOC production is prior to and during spore production and mycotoxin production

76 Mycotoxins Produced to inhibit or kill competitors
May cause serious short term and long term health effects Over 200 recognized mycotoxins, and many more not yet discovered Toxins production varies with the species, the conditions and the substrate

77 General Health Effects
Sinus congestion Sneezing Coughing, Eye irritation Asthma Bronchitis Hypersensitivity pneumonitis Infectious diseases, e.g. ringworm, athletes foot, nail infections, Histoplasmosis, Valley Fever Histoplasmosis Caused by Histoplasma capsulatum Organism often found in soil enriched by bird droppings; Effects are usually mild flu-like illness; possibly pneumonia, blindness, and death Valley Fever – caused by Coccidioides immites; carried in dust

78 Mycotoxin Health Effects
Mucous membrane irritation Cold and flu symptoms Sore throat Headache Fatigue Diarrhea Skin rashes Dizziness Nausea Immunosuppression Birth defects Tremors Hemorrhaging Cytotoxicity Hepatotoxicity Nephrotoxicity Cancer

79 Aflatoxin One of the most potent carcinogens known to man
Linked to a variety of health problems FDA maximum allowable level is 20 ppb Produced by some species of Aspergillus

80 T-2 Toxin A tricothecene toxin Produced by species of Fusarium mold
One of the more deadly toxins Ingestion in sufficient quantity can cause rapid death due to internal hemorrhage Implicated in alimentary toxic aleukia and pulmonary hemosiderosis Damage is often permanent

81 Fumonisin Associated with some species of Fusarium mold
Commonly found in corn Has resulted in dozens of deaths of horses and swine Causes “crazy horse disease” or leukoencephalomalcia, a liquifaction of the brain Chronic low-level exposure in humans has been linked to esophageal cancer

82 Satratoxin H Produced by Stachybotrys, Trichoderma and other molds
High doses or chronic low doses are lethal Abortogenic in animals Believed to alter the immune system function

83 Stachybotrys chartarum (atra)
Grows on building material with high cellulose content and low nitrogen content Optimum water activity is 0.94 Areas with relative humidity above 55% and subject to temperature fluctuations are ideal for toxin production Changing humidity may induce heavy sporulation Spores are covered with slime; not easily airborne

84 Stachybotrys Effects Chronic exposure effects: cold and flu symptoms, sore throats, diarrhea, headaches, fatigue, dermatitis, intermittent local hair loss, generalized malaise Toxins suppress the immune system, affecting lymphoid tissue and bone marrow Produces several highly toxic tricothecene mycotoxins, including Satratoxin G Horses in Ukraine in 1930’s had outbreak of disease characterized by shock, dermal necrosis, leukopenia, hemorrhage, nervous disorders and death. Scientists determined that the disease was caused by Stachybotrys growing on the straw and grain fed to the animals. Contents of one petri plate resulted in sickness, and contents of 30 plates resulted in death. 1mg. of pure toxin is reported to cause death. People working with the contaminated hay or feed had dermatitis, pain and inflammation of the mucous membranes of the mouth and throat, a burning sensation of the nasal passages, tightness of the chest, cough, bloody rhinitis, fever, headache and fatigue Outbreak in of hemosiderosis in Cleveland infants. Ten cases reported. Age range 4 weeks to 16 weeks. One infant died, age 9 weeks. All homes of the infants had high levels of total fungi and Stachybotrys. The homes had previously sustained water damage, resulting in mold contamination.

85 Stachybotrys Effects (cont.)
Animals injected with Stachybotrys exhibited necrosis and hemorrhage within the brain, thymus, spleen, intestine, lung, heart, lymph node, liver and kidney Toxin is reported to be a liver and kidney carcinogen

86 Stachybotrys - contaminated straw and normal straw

87 Stachybotrys and other mold on sheetrock
Stachybotrys and other fungi on sheetrock of flooded school basement. Growth occurred about one week after flooding.

88 Stachybotrys in ventilation tunnel
Stachy on gypsum wallboard (covering insulation on a concrete wall), inside ventilation tunnel around the base of an elementary school. Tunnel was flooded about 6 inches deep.

89 Stachybotrys on fiberglass insulation backing
Building had roof leak that dripped onto ceiling (left) and insulation. Paper backing of insulation was against paper backing of sheetrock of ceiling.

90 Water-Damaged Ceiling

91 Flooded Room After Remediation

92 Water-Damaged Wallpaper

93 Stachybotrys, Aspergillus and Penicillium in Basement


95 Difficulties in Mold Sampling
No TLVs or PELs Fungus might not be producing spores at the time of sampling Spores might be adhering to surfaces rather than airborne Spores might not survive impaction Spores might not grow on the media used Colonies might be overgrown by others and not detected Organism might be very slow growing

96 Types of Mold Sampling Bulk samples Surface samples - tape
Surface samples - swab Air samples using impaction onto agar Air samples using spore trap methods

97 When Sampling Results Indicate Serious Mold Problem
Total indoor levels are higher than total outdoor levels Fungi indoors are different from outdoors or non-complaint areas Fungi are allergenic or toxigenic Area is likely to be disturbed Present or past water or high humidity

98 Key Remediation Steps Correct the moisture problem that led to the mold growth Remove all contaminated porous materials Use proper PPE Containment and negative pressure to prevent spread of spores Minimize dust production Decontamination Correct problem, e.g. roof leaks, drainage situation that causes flooding Remove porous materials, according to NY City and EPA Guidelines

99 Key Remediation Steps (cont.)
Clean all contaminated non-porous materials HEPA vacuum Disinfectant or soap and water

100 Personal Protective Equipment for Remediation Work
For minimal mold growth N-95 respirator Gloves For moderate to extensive mold growth Eye protection Full-body covering

101 Remediation Resources
NY City Department of Health Guidelines on Assessment and Remediation of Fungi in Indoor Environments Mold Remediation in School and Commercial Buildings (EPA)

102 Remediation and General Information Resources
Mold in My Home: What Do I Do? Mold in My School: What Do I do? Mold in Indoor Workplaces

103 QUIZ What is the first thing you should look for when there is a suspected mold problem? What kind of personal protective equipment should you wear if you are removing moldy sheetrock?


105 Ventilation Purpose - Remove or dilute airborne contaminants
Supply air - mixture of outside air and re-circulated air

106 HVAC Systems Components Air intakes, dampers, filters
Heating & cooling units, coils, drain pans Ductwork Supply vents Exhaust vents Plenum

107 ASHRAE Outdoor Airflow Requirements, 62.1-2004
Vbz = RpPz+RaAz Vbz = Breathing zone outdoor airflow Rp = Outdoor airflow rate required per person as determined from Table 6-1 Pz = zone population Ra = Outdoor airflow rate required per unit area as determined from Table 6-1 Az = zone floor area

108 Acceptable Temperature Ranges, ASHRAE 62.1-2004
Dry bulb at 30% relative humidity: Winter: 68.5ºF – 76.0ºF Summer: 74.0ºF – 80.0ºF

109 When Good HVAC Systems Go Bad
Poorly balanced systems Areas with stale air Drafty areas Contaminant buildup Uncomfortable temperatures Odors from other areas of the building

110 Poorly Located Air Intakes
Entrainment of vehicle exhaust from parking areas Entrainment of bioaerosols from debris on the ground Entrainment of exhaust from adjacent roof vents, e.g. HVAC system, sewer

111 Poor Filters or Poor Filter Maintenance
Excessive dust and dirt in the supplied air Insects Mold spores

112 Ductwork Leaks Duct liners Energy loss
Can draw contaminants into ducts Duct liners Can degrade; particles enter supplied air

113 Backdrafting Pressure imbalance
Air to air heat exchanger cracks Duct leakage Tight building Combustion contaminants are drawn into the building

114 Ventilation to Meet Occupant Needs
ASHRAE Standards Temperature Relative Humidity Minimum outdoor air requirements CO2 levels below 1000 ppm Outdoor air supplied at 15 cfm/person

115 Ventilation – Engineering Controls
Modify ventilation system Modify pressure relationships Filters Ion generators Humidification systems

116 IAQ Inspection DVD

117 QUIZ How often should ducts be cleaned?
What level of carbon dioxide indicates adequate ventilation? Should a shop area be at positive or negative pressure relative to the rest of the building?


119 Challenges When Evaluating IAQ Problems
Contaminants and their sources are not always obvious Problems may be cyclical or episodic Only a few employees may complain of a problem The situation may become emotionally charged

120 IAQ Inspection Steps Building history Brief walk-through Symptoms
Air monitoring Report, with recommendations

121 Questionnaires Can identify the cause of many IAQ problems
Building history questionnaires Symptoms questionnaires HVAC questionnaires

122 EPA’s I-BEAM Software Available on the Internet at:

123 Walk-Through Inspection
Outside sources Building exterior HVAC system Boiler room Attic Crawlspace Occupied spaces Wall cavities Storage spaces Outside air – nearby farming or disturbance of plant materials excavation or construction wastewater treatment irrigation composting Building exterior – Poor grading or water drainage perforations cracks in building blocked rain gutters wood rot animal infestations near or below building sprinklers that wet exterior walls HVAC – Air intakes filters heat exchangers dirty coils excessive water in condensate pans dampness and growth on acoustical lining poorly maintained air washers or humidifiers supply plenums and ductwork supply air diffusers Occupied space – water damage chronic condensation window air conditioners and evaporative air coolers fancoil and induction units potted plants carpet fabric office partitions wall coverings drapes upholstered furniture portable humidifiers return air plenums

124 Look Into: Ceilings, walls, floors, furnishings Water damage Odors
Remodeling Insulation falling into work area Plumbing leaks and mold in crawlspaces

125 Look Into: Fluorescent light fixtures Frequently damp areas
Pets & aquariums Humidifiers Backdrafting possiblilities Ergonomic factors Stress & tension

126 Mold in basement

127 Vinyl wall-covering, after flooding

128 Poor Outside Drainage Design

129 Ceiling mold

130 Moldy wall

131 Ceiling Tile Stain

132 Mold on AC Ductwork

133 Mold in Laundry Room

134 IAQ Tools EPA’s “Building Air Quality” EPA’s “Tools for Schools”
I-BEAM software Monitoring equipment

135 Monitoring Basic Parameters
CO CO2 Temperature Relative humidity Air flow rates

136 Formaldehyde Sampling

137 Ventilation “Dilution is the solution”
“When all else fails, ventilate”


Download ppt "Occupational Safety and Health Bureau"

Similar presentations

Ads by Google