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T EDD N ATHANSON, P. Eng. Indoor Air Quality Consultant Tedd@IAQconsultant.com (613) 558 - 4545. I NDOOR A IR Q UALITY. Union of Taxation Employees November, 2010. Agenda. General IAQ Introduction New Initiatives ; Codes, Standards, Guidelines What we want / have / can do
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TEDDNATHANSON, P. Eng. Indoor Air Quality Consultant Tedd@IAQconsultant.com (613) 558 - 4545 INDOOR AIR QUALITY Union of Taxation Employees November, 2010
Agenda • General IAQ Introduction • New Initiatives ; Codes, Standards, Guidelines • What we want / have / can do • VOCs , Microbials, etc. • Future trends, Conclusions
AIR 78.1% 20.9% 0.9% 0.1% 100% NITROGEN OXYGEN ARGON 0.035 (CO2) 0.065 Mixture
IAQ FACTORS Outdoor Air Quality: Gases, Particulates, Seasons, Locations Indoor Air Quality: Building Envelope, Materials, Furnishings, Occupant Density and Activities, Processes HVAC System: Design, Operation and Maintenance
IAQ Pollutants / Stressors • Pollutants - carbon monoxide, formaldehyde, VOCs, particulates, microbials • Stressors - temperature, RH, odours, air motion/circulation, noise, lighting, vibration, privacy, housekeeping, social • Solutions - source control, ventilation, air flow (P), isolation, time of use, sealing, substitution
INDOOR AIR QUALITY (IAQ) Physical, chemical and biological characteristics of indoor air that can effect the comfort and health of the occupant. ASHRAE TLV ppm ACGIH VOC ppb SBS TVOC HVAC
CANADA LABOUR CODE: PART II Every employer shall insure that the safety and health at work of every person employed by the employer is protected [124]; Ensure that all permanent and temporary buildings and structures meet the prescribed standards [125 (a)]; Ensure that the levels of ventilation, lighting, temperature, humidity, sound and vibration are in accordance with prescribed standards [125 (1) (n)]; and Ensure that concentrations of hazardous substances in the workplace are controlled in accordance with prescribed standards [125.1(a)].
LABOUR CANADA, PART II OSH REGULATIONS Revised in 2000, Division 3 : HVAC Systems • Built or when modified, to meet ASHRAE 62 - 1989 “as amended” • Design information to be available • All systems to have operating, inspection, testing, cleaning, maintenance and calibration instructions • Reports to be prepared by a "qualified person" and posted • IAQ investigation to be done when warranted (Technical Guide)
STANDARDS ACGIH, Threshold Limit Values, Chemical Substances and Physical Agents ASHRAE 62, Ventilation for Acceptable Indoor Air Quality (under continuous revision) ASHRAE 55, Thermal Environmental Conditions for Human Occupancy
Guidelines, Good Practices, Policies • Health Canada, IAQ in Office Buildings: A Technical Guide, 1995 • CSA Z2044-94, Guidelines for Managing IAQ in Office Buildings • Canadian Construction Association, Mould Remediation Guidelines, 2004 • Health Canada, Fungal Contamination in Public Buildings, 1995, 2004 • Duty to Accommodate
BUILDING RELATED HEALTH EFFECTS Building Related Illness Sick Building Syndrome Mass Psychologic Illness Multiple Chemical Sensitivity, Environmental Sensitivity
SICK BUILDING SYNDROME • Eye, nose throat irritation • Headache • Fatigue • Reduced concentration • Irritability • Dry skin • Nose bleeds
SBS SBS is a multifactorial problem involving chemical, microbiolgical, physical, and psychological mechanisms. The syndrome may represent overlapping sets of symptoms involving multiple causes and physiologic pathways. Until we identify specific causes, appropriate mitigation and prevention of building-related symptoms may need to be at the level of prudent design, operation, and maintenance practices, focused on factors which reduce the likelihood of problem indoor exposures and conditions. Mendel, 1994
52% DUE TO CONTAMINATION • Microbials • VOC's, Formaldehyde • Carbon Monoxide • Particulates
48% DUE TO VENTILATION • Improve Operation • Lack of Maintenance • Poor Circulation • Exhaust Re-entrainment • High Temperature • Low Relative Humidity • High Carbon Dioxide
GOAL - to provide a healthy comfortable and productive workplace
IAQ AND PRODUCTIVITY $/sq.ft./y Construction Cost: Land, Design & Construction: $16.00 Furnishings and Office Equipment: $15.90 Operating: Utilities $2.00 Janitorial $1.00 Taxes and Insurance $2.00 Management, Services, Vacancies $3.50 $8.50 Employee Costs: Salaries & Benefits: $265.00 Indoor Air Quality Update, August 1989, Amortized at 9% for 30 years
Employee productivity loss attributable to IAQ is estimated to be 3% (14 min/day) and 0.6 added sick days annually. Understanding Indoor Quality, Brooks and Davis Ref.: J. Woods, 1989, Occup. Med. State Art Rev.
IAQ STANDARDS AND REGULATIONS "You don't have to know everything before you do anything" -- James Scheurer (D-NY)
ASSESSMENT STRATEGY IAQ Factors and Issues Stage 1: Walkthrough, inspection, discussion, solution? Stage 2: Measurement
STAGE 2 HVAC AND IAQ ASSESSMENT • System Design, Capacity, Performance • IAQ Measurements: • Temperature, relative humidity • Carbon Dioxide (ventilation rate) • Carbon Monoxide (pollution intrainment) • Particulates • Volatile Organic Compounds (VOCs) • Microbials (moisture content)
VOLATILE ORGANIC COMPOUNDS (VOC’S) • Off-gassing of chemicals from new materials - construction and renovation • Sources: • structural; particle board, glues, paints • furnishings; carpets, computers, furniture • consumer products; perfume, shampoo, cleaning agents • pesticides, disinfectants, etc.
TVOC >3 mg/m³ perceived odour intensity, mucous membrane irritation, concentration ability reduced >8 mg/m³ degraded air quality, ventilation, dryness >25 mg/m³ significant irritation of eyes, nose and throat, confusion, fatigue PWGSC 1 mg/m³ target5 mg/m³ action level
Biological Agents& Sources • Bacteria : humans / water / food • Fungi or mould: plants / soil / food • Viruses : humans / animals • Allergens/Antigens : animals (pets), cockroach / mites, by-products of bacteria (endotoxins) and moulds (MVOCs, mycotoxins and fragments).
MICROBIAL SOURCES • Wet carpet, ceiling tiles, insulation, walls (condensation, leaks, floods) • Spray humidifiers, reservoirs • Condensate pans • Water towers dirt + WATER = Microbial Growth
Pro - Active Measures to Avoid Microbial Contamination • Moisture Control in buildings and systems ~ design, construction, operation, maintenance and use. • Dust/dirt control through good HVAC O&M, and housekeeping • Water Damage Restoration
FLOOD REMEDIATION Microbial contamination does not need to follow water damage. • A rapid response to contain and limit water damage, the removal of soiled substrates, cleaning and drying, will provide limited opportunity for microbial growth. • No need to sample if mould is visible.
No Regulated Exposure TLVs for Mould • Wide variation in individual susceptibility: genetics, age, health, past exposure at home /work, etc. • The effects of other agents and secondary by-products are unknown and few biological markers exist. • Few epidemiological studies regarding dose-response relationship. Anecdotal cases.
No Regulated Exposure TLVs for Mould (con’t) • Different sampling methods: equipment, time and period, spore type and size, (viable/non-viable) collection media (agar/slides), incubation time and temperature. • Collection methods do not reflect actual human exposure
Exposure and Risk • Must be airborne (inhaled, contacted, or ingested) • Depends on the species type, viability (allergenic, toxigenic, pathogenic) • Depends on amount ( time) • Depends on susceptibility Therefore no “threshold” - however, it is prudent to minimize exposure.
Legal Precedent : 1989, Hospital, St. Foy, Quebec. “Mould should not grow in buildings.” [adapted by PWGSC, U.S.EPA, Canadian Construction Association, etc.] CMHC (1993) : “People should not live in moldy houses.”
Mould Exposure Guidelines • Visible or hidden microbial growth within a structure is not acceptable. • Indoor quantities should be lower than outdoors, and reflect the same rank order (biodiversity). • The confirmed presence* of toxigenic species requires risk management according to established guidelines. * defined by AIHA
OTHER “Problems” • Histoplasma capulatum : a soil fungi that grows with bird and bat excrement. Causes histoplasmosis, a lung disease. • Hantavirus : airborne viral infection found in urine, saliva or droppings of infected deer mice, can be fatal. (BC) • Anthrax : bacteria, Bacillus anthracis, affecting grazing animals, toxic. • Escherichia coli : bacteria found in feces. Total Coliforms (water quality). • TB, SARS, etc. from third-world countries • Lead in drinking water and in paint
SENSITIZATION After an initial exposure to a particular allergen, an individual who develops an allergy becomes "sensitized" to that allergen. Subsequent lower exposures may elicit a reaction
Environmental Sensitivity • ES may be classified as a disability ? • Employer has a ‘duty to accommodate’ and employees have a ‘right to work’. • Employer must do so until the point of “undue hardship”. • This requires ‘one good try’ to accommodate. • Need support & cooperation of all.
LEGIONELLA: Pneumonia American Legion Conventions, Philadelphia 1976 Bellevue Stratford Hotel; (182 affected, 29 died} Contaminated humidifiers, wet surfaces, hot water systems, hot tubs, vaporizers, cooling towers, condensers
OZONE (O3) TOXIC Health Effects: lung and immune system irritation, dryness of eyes, nose and throat FDA max. acceptable level 50 ppb health effects 60 - 80 ppb ACGIH ceiling, TLV 100 ppb smell threshold 5 - 2000 ppb (olfactory fatigue)
PCB's: Polychlorinated Biphenyls (Chlorodiphenyls) electric transformers, capacitors, ballasts hydraulic fluids, oils ACGIH TLV 1 - 0.5 mg/m³ NIOSH TWA 1 - mg/m³, carcinogen
ASBESTOS • Insulation: pipe, walls, ceilings, ducts, boilers • Ceiling and floor tiles • Plaster and paints • Pro-active management program for disturbance, retrofit "Intact and undisturbed asbestos materials do not pose a health risk" EPA, NIOSH, OSHA
RADON Decay of Radium Þ particles, colourless, odourless HC: 800 Becquerels/m³ action level, has been reduced to 200 in 2007.
New or Retrofitted Buildings • Select low-emitting, low solvent content, less toxic, less odourous products. Review manufacturers' specifications and the material safety data sheets (MSDS). • Properly commission the building or space. ASHRAE Guideline 1-1989, Guideline for Commissioning of HVAC Systems, is a good reference document. • Phase in products, finishing and furnishings over different time periods so as not to create a "sink" (e.g., VOCs from carpets absorbing onto partitions). Ideally, products should off-gas at the manufacturer or in off-site storage and should not be plastic wrapped after assembly.
New or Retrofitted Buildings (cont'd)` • Increase the ventilation rate as much as possible over several weeks after installation. Run the ventilation system 24 hours a day until odours are gone. It is a good idea to open a window to exhaust pollutants during renovation, while blocking-off the returns. Schedule retrofit activity in the spring or fall, when more outside air can be supplied. If work is done over the weekend, do not shut off the ventilation system. • Monitor the total VOC (TVOC) levels and occupy space only when levels are below a certain limit (perhaps 5 mg/m³). • Establish a communication plan with the occupants, detailing the work to be done, the timetable and the method of addressing IAQ issues. Provide a contact person's name, phone number and E-mail address if applicable.
IAQ and the Future • Compliance and due diligence – building environmental audits. • Legal, liability, and insurance issues -- worker’s compensation, risk assessment, duty of building owner, employer, professionals, and trades. Certification. • Materials selection -- emissions, offgassing, “green products”. LEED (Leadership in Energy and Environmental Design) certified buildings. • Information and awareness -- WWW, court cases, news media, more “consultants and experts”.
Conclusions • Many IAQ problems can be prevented by educating facility management, staff and occupants about IAQ issues and factors. • The expense and effort required to prevent most IAQ problems is much less than that required to resolve problems after they develop. • When IAQ problems do arise, they can often be resolved using skills that are available in-house. • If outside assistance is needed to solve an IAQ problem, the best results will be achieved if building owners, managers and occupants are informed consumers. • Open and full communication is part of the successful resolution of an IAQ problem.