Present OSHA sampling and analytical procedures were developed to meet precision and accuracy requirements for airborne contaminants in the range of OSHA Permissible Exposure Limits (PEL's) and American Conference of Governmental Industrial Hygienists (ACGIH) Threshold Limit Values (TLV's). Microorganisms and Other Biological Contaminants (Microbials). McLellan, R. K. 1983. (h) ACGIH Threshold Limit Values (TLVs) (ACGIH). 1. In addition, the concept of lowering "total VOC" (TVOC) does not always assure safer products because the individual VOCs that make up TVOC can vary widely in their toxicity. Applied Industrial Hygiene 2(5):RIO to R16. CO is an . OSHA's Hazard Communication standard (1910.1200 Appendix D) requires that safety data sheets list not only the relevant OSHA PEL but also the ACGIH TLV and any other exposure limit used or recommended by the chemical manufacturer, importer, or employer preparing the safety data sheet. The combined effects of multiple, low-level air contaminants have not been investigated thoroughly and may be a cause of the problem. Appendix III:2-1 presents a brief discussion of these items. NIOSH RELs are authoritative Federal agency recommendations established according to the legislative mandate for NIOSH to recommend standards to OSHA. These symptoms often disappear when the employee leaves the workplace. The TLVs and BEIs are copyrighted by ACGIH and are not publicly available. Are any employees obtaining medical care? Department of Health and Human Services. In addition to the values listed in this table, the Z tables in 29 CFR 1910.1000 list skin absorption designations. Most indoor air particulates are due to tobacco smoke and are in the respirable range. Occupational Safety & Health Administration, Occupational Safety and Health Administration, Outreach Training Program (10- and 30-hour Cards), OSHA Training Institute Education Centers, Directorate of Technical Support and Emergency Management, Technical Equipment: On-site Measurements, Polymer Matrix Materials: Advanced Composites. For example, the World Health Organization (WHO) categorizes indoor organic pollutants as: 1987. Tobacco smoke contains several hundred toxic substances including carbon monoxide, nitrogen dioxide, hydrogen sulfide, formaldehyde, ammonia, benzene, benzo(a)pyrene, tars, and nicotine. Enforcement is based on the substance name. Acute health effects: Eye, respiratory tract, mucous membrane irritation; aggravation of chronic respiratory diseases. Sources: Paints, cleaning compounds, moth-balls, glues, photocopiers, "spirit" duplicators, signature machines, silicone caulking materials, insecticides, herbicides, combustion products, asphalt, gasoline vapors, tobacco smoke, dried out floor drains, cosmetics and other personal products. These office-related health problems can be evaluated by a consultant through employee interviews, analysis of job demands, and training employees. 1987, 1988. Steps to Reduce Exposure to Carbon Monoxide Although OSHA does not have IAQ standards, it does have standards about ventilation and standards on some of the air contaminants that can be involved in IAQ problems. The tables list air concentration limits, but do not include notations for skin absorption or sensitization. Lioy, P. J. Provides information about investigating IAQ issues and controlling IAQ in the workplace. OSHA's former limit for carbon dioxide was 5000 ppm as an 8-hour TWA. The TLVs and BEIs are copyrighted by ACGIH and are not publicly available. With low oxygen levels being the biggest cause of death in confined spaces, accurate oxygen level measurements are essential. acceptable levels: < 600 ppm complaints of stuffiness and odors: 600 - 1000 ppm ASHRAE and OSHA standards: 1000 ppm general drowsiness: 1000 - 2500 ppm adverse health effects may be expected: 2500 - 5000 ppm maximum allowed concentration within a 8 hour working period: 5000 - 10000 ppm This is equivalent to approximately 15 ppm diesel vapor. California Division of Occupational Safety and Health (Cal/OSHA) Table AC-1, Permissible Exposure Limits (PELs), in California Code of Regulations (CCR) Title 8 Section 5155, last viewed October 2, 2019. To illustrate the formula prescribed in paragraph (d)(2)(i) of this section, consider the following exposures: Substituting in the formula, we have: Sources: Air handling system condensate, cooling towers, water damaged materials, high humidity indoor areas, damp organic material and porous wet surfaces, humidifiers, hot water systems, outdoor excavations, plants, animal excreta, animals and insects, food and food products. [71 FR 16673, April 3, 2006; 81 FR 16861, March 25, 2016], Occupational Safety & Health Administration. 1975. Health Effects and Sources of Indoor Air Pollution. Enforcement is based on the substance name. Click here for permission request form. Personal Correspondence to Long Loo, Occupational Safety and Health Administration. The following are general recommendations which, where relevant, should be standard procedure. Airborne Microorganisms. RELs are for up to 10-hour time weighted averages (TWAs) during a 40-hour work week unless otherwise indicated. Industrial experience, new developments in technology, and scientific data clearly indicate that in many instances these adopted limits are not sufficiently protective of worker health. When entry is in this column only, the value is exact; when listed with a ppm entry, it is approximate. 43. TVOC can be measured in micrograms per cubic meter (g/m3) of air, milligrams per cubic meter (mg/m3), parts per million (ppm) or parts per billion (ppb). In case of a mixture of air contaminants an employer shall compute the equivalent exposure as follows: Based on screening results, validated sampling procedures may be required to further quantify employee exposures. Volatile Organic Compounds (VOC's). (e) Milligrams of substance per cubic meter of air. These levels are only guidelines. Collect screening samples using detector tubes or direct reading instruments. What is the magnitude and distribution of employee complaints or illnesses? Sampling and Analytical Methods, Severe Storm and Flood Recovery Assistance, OSHA Technical Manual (OTM) - Section III: Chapter 2. 250 to 2000 ppb Look for VOC sources if this average level persists for a month. NIOSH has established occupational exposure limits for compounds not included in the OSHA Z Tables. 1987. . At present, specialized bioaerosol sampling equipment is available through the OSHA Health Response Team. OSHA dictates that the minimum "safe level" of oxygen in a confined space is 19.5%, while the maximum "safe level" of oxygen in a confined space is 23.5%. Contamination from outside building - 10%. Since 81.25 ppm is less than 100 ppm, the 8-hour time weighted average limit, the exposure is acceptable. When possible, use local exhaust ventilation and enclosure to capture and remove contaminants generated by specific processes. Two hours exposure at 150 ppm Two hours exposure at 75 ppm Four hours exposure at 50 ppm Substituting this information in the formula, we have (2 150 + 2 75 + 4 50) 8 = 81.25 ppm Since 81.25 ppm is less than 100 ppm, the 8-hour time weighted average limit, the exposure is acceptable. See 1910.1028 for specific circumstances. Acetone Acetone is prevalent in polish and in most homes can be found in furniture polish, wallpaper and nail polish. (c) The CAS number is for information only. Much of the information on validated sampling and analytical methods is contained in the OSHA Chemical Information Manual or in the OSHA Analytical Methods Manual. Sources: X-ray development equipment, silicone caulking compounds. TLV: between 750 and 1,000 ppm (7). . Sources of these compounds include solvents, liquid fuels, furniture, carpets and other fabrics. Are there sources of indoor contaminants that could lead to employee complaints (e.g., copy machines, signature machines, blueprint copiers, paints, cleaning compounds and disinfectants, tobacco smoke, adhesives and glues, off-gassing of construction material and building fabric, contaminants generated by construction or renovation, positive- or negative-pressure work areas, improperly vented gas appliances, air fresheners, pesticides)? Please see ACGIHDocumentation for additional limits, skin absorption and other designations, and explanations. OSHA enforces these limits under section 5 (a) (2) of the OSH Act. However, levels at poultry plant inspectionstations range from about 900 to 3,500 ppm (depending on how close the inspection station is to the dry . However, OSHA recommends that employers consider using the alternative occupational exposure limits because the Agency believes that exposures above some of these alternative occupational exposure limits may be hazardous to workers, even when the exposure levels are in compliance with the relevant PELs. The ACGIH5 recommends a pre-assessment of the extent of microbial contamination prior to initiation of air sampling. Typical levels of carbon monoxide in offices are 0 to 5 ppm [Illinois Department of Public Health 2018]. Recommendations include programs that change the behavioral patterns of occupants. The General Duty Clause of the OSH Act (the law that created OSHA) requires employers to provide workers with a safe workplace that does not have any known hazards that cause or are likely to cause death or serious injury. National Institute for Occupational Safety and Health (NIOSH). Sources: Copy machines, electrostatic air cleaners, electrical arcing, smog. Although OSHA does not define a STEL or ceiling value for CO, NIOSH does, and it is 200 ppm. Example. If ventilation is turned off during weekends or other periods, ensure that system is on so that contaminant concentrations are sufficiently diluted prior to occupancy. For more information on TLVs, please go to https://www.acgih.org/TLV/. See Important Note on ACGIH TLVs, which is also reprinted with permission from ACGIH. 1987. This document contains a high level discussion of indoor air quality given that ASHRAE has published many informative documents related to indoor air quality such as the Handbook -- Fundamentals (ASHRAE 2017a) (particularly Chapters 9 through 12) and two IAQ guides: "Indoor Air Quality Guide - Best Practices for Design, Construction and From 0.5 mg/m3 of TVOC concentration level onwards the concern is considered to be considerable or high. Where: ASHRAE 62-1989: Standards for Acceptable Indoor Air Quality. Whenever respirators are used, their use shall comply with 1910.134. American Society for Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE). The shaded area of this page lists other occupational exposure limits (OELs) from Cal/OSHA, NIOSH, and ACGIH. Web site accessed on October 18, 2019. 3, 2006; 71 FR 36008, June 23, 2006.]. Walsh, P. J., Dudney, C. S., and Copenhover, E. D. 1984. Levels of carbon monoxide inside buildings should not exceed 9 ppm. Carbon Dioxide. Investigators may need to discuss the operation of the ventilation system with building engineers and perform ventilation testing to determine proper fresh air intake. For increased sensitivity, higher flow rates or longer sampling times may be used. New York: John Wiley & Sons. (j) The final benzene standard in 1910.1028 applies to all occupational exposures to benzene except in some circumstances the distribution and sale of fuels, sealed containers and pipelines, coke production, oil and gas drilling and production, natural gas processing, and the percentage exclusion for liquid mixtures; for the excepted subsegments, the benzene limits in Table Z-2 apply. Before biological sampling, several precautions must be taken including making arrangements for preparing culture media for sampling, specialized shipping procedures, and making arrangements for analysis by a laboratory familiar with the handling and processing of biological samples. ASHRAE Standard 62-73: Standards for Natural and Mechanical Ventilation. These organizations periodically make revisions to their OELs and so they should be consulted directly for their most current values and substances, as well as special notations such as for skin absorption. (n) See Table Z2 for the exposure limits for any operations or sectors where the exposure limits in 1910.1024 are stayed or otherwise not in effect. During the walkaround inspection, professional judgment must be exercised to determine if samples should be collected to evaluate potential sources and potential contaminants including gases, vapors, and particulates. Diesel vapor. ASHRAE Standard 90-75: Energy Conservation in New Building Design. > 2000 ppb The VOC contents are very high - consider taking action/ventilating right now. Isolate, if feasible, areas of renovation, painting, carpet laying, pesticide application, etc., from occupied areas that are not under construction. NIOSH has a TWA REL of 10,000 ppm with a 10-minute 30,000-ppm ceiling limit; however, NIOSH (Ex. Boston: Addison-Wesley. RELs are for up to 10-hour time weighted averages (TWAs) during a 40-hour work week unless otherwise indicated. ASHRAE Standard 55-1981. The following potential problems may need to be addressed: NOTE: Referenced OSHA procedures can be found in the OSHA Analytical Methods Manual or the OSHA Chemical Information Manual. 1989. Cal/OSHA sets a TWA at 25 ppm, and a ceiling at 200 ppm. Acute health effects: Irritation to the eyes, skin and lungs; dermatitis. Viewable at http://www.dir.ca.gov/title8/5155table_ac1.html. Use a particle counting instrument capable of measuring concentrations as low as 2,000 particles/cubic centimeter (cc) of air for comparing particulates in various areas. New York: ASHRAE. Volatile Organic Compounds (VOCs): 0 - 15 ppm Volatile organic compounds (VOCs) are chemical compounds that can evaporate under normal indoor conditions of temperature and pressure. The TLV and BEIBook and Documentation of the Threshold Limit Values on Chemical Substances, 7th Edition are available through the ACGIH website at http://www.acgih.org. 1910.1026, is stayed or is otherwise not in effect. Table Z-2. These include averaging periods, size selective measures and similar information. (i) This standard applies to any operations or sectors for which the exposure limits in the beryllium standard, 1910.1024, are stayed or is otherwise not in effect. Cal/OSHA has established an extensive list of PELs (Cal/OSHA AC-1 Table) that are enforced in workplaces under its jurisdiction. However, they can be purchased in their entirety on the ACGIH website at http://www.acgih.org/store/. Provides links and references to additional resources related to indoor air quality. measured as high as 25,000 to 30,000 ppm. The following States have Indoor Air regulations: California New Jersey Maintain indoor air relative humidity below 60% (50% where cold surfaces are in contact with room air). TLVs and BEIs are not publicly available, but can be purchased on ACGIH's website. B. What are the design and operational parameters of the heating, ventilating, and air-conditioning (HVAC) system, such as source and amount of fresh air per occupant delivered to the breathing zone; adjustable or local HVAC controls; type of humidifier and how controlled; recent ventilation changes; and areas serviced by various units? ACGIH Committee on Bioaerosols, American Conference of Governmental Industrial Hygienists. Guidance for Indoor Air Quality Investigations. Many large industrial organizations have felt obligated to supplement the existing OSHA PELs with their own internal corporate guidelines. Em= 0.925 The synergistic effect of multiple stressors appears to indicate that building-related problems may be more than an air quality problem. E = (Ca Ta + Cb Tb + . National Institute for Occupational Safety and Health (NIOSH) (2019) NIOSH Pocket Guide to Chemical Hazards. The annotated tables contain links to the complete OEL lists from Cal/OSHA and NIOSH. (i) This standard applies to any operations or sectors for which the exposure limits in the beryllium standard, 1910.1024, are stayed or is otherwise not in effect. ASHRAE Position Document on Indoor Carbon Dioxide 1 ABSTRACT Indoor carbon dioxide (CO 2) has played a key role in di scussions of ventilation and indoor air quality (IAQ) for centuries. Sampling methods and equipment are covered in. Much of the specialized equipment is available through the OSHA Health Response Team (HRT), Cincinnati Technical Center (CTC), or Regional Offices. The quality of indoor air inside offices, schools, and other workplaces is important not only for workers' comfort but also for their health. Acute health effects: Nausea; dizziness; eye, respiratory tract, and mucous membrane irritation; headache; fatigue. Indoor Pollution: Guidelines for Prevention and Control of Microbiological Respiratory Hazards Associated with Air Conditioning and Ventilation System. (i) In 29 CFR 1000, all inert or nuisance dusts, whether mineral, inorganic, or organic, not listed specifically by substance name are covered by the Particulates Not Otherwise Regulated (PNOR) limit which is the same as the inert or nuisance dust limit of Table Z-3. The U.S. National Ambient Air Quality Standards for CO are 9 ppm for 8 hours and 35 ppm for 1 hour. The type and concentrations of the airborne microorganisms will determine the hazard to employees. The OSHA Health Response Team may be consulted for further information. Sources: Off-gassing from urea formaldehyde foam insulation, plywood, particle board, and paneling; carpeting and fabric; glues and adhesives; and combustion products including tobacco smoke. In particular, ACGIH provides an explanation of the use of TLVs and access to documentation. The Cal/OSHA AC-1 table and regulations should be consulted for explanations. 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