Tobacco Education Center

Can Ventilation Control Secondhand Smoke? (2000)

An Analysis of the Document "Proceedings of the Workshop on Ventilation Engineering Controls for Environmental Tobacco Smoke in the Hospitality Industry", sponsored by the Federal Occupational Safety and Health Administration and theAmerican Conference of Governmental Industrial Hygienists. June 2000
By James Repace, Msc, Health Physicist Repace Associates, Inc.
Secondhand Smoke Consultants
101 Felicia Lane Bowie, MD 20720

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A panel of ventilation experts assembled by OSHA and ACGIH concluded that dilution ventilation, used in virtually all mechanically ventilated buildings, will not control secondhand smoke in the hospitality industry (e.g., restaurants, bars, casinos). The panelists asserted that a new and unproved technology, displacement ventilation, offered the potential for up to 90% reductions in ETS levels relative to dilution technology. However, this assertion was not substantiated by any supporting data. Air cleaning was judged to be somewhere between dilution and displacement ventilation in efficacy, depending on the level of maintenance. The panel also failed to quantify the ETS exposure or risk for workers or patrons either before or after the application of the new technology. Panelists observed that building ventilation codes are not routinely enforced. They also noted the lack of recognized standards for acceptable ETS exposure as well as the lack of information on typical exposure levels. However, indoor air quality standards for ETS have been proposed in the scientific literature, and reliable mathematical models exist for predicting pollutant concentrations from indoor smoking. These proposed standards and models permit application of an indoor air quality procedure for determining ventilation rates as set forth in ASHRAE Standard 62. Using this procedure, it is clear that dilution ventilation, air cleaning, or displacement ventilation technology even under moderate smoking conditions cannot control ETS risk to de minimis levels for workers or patrons in hospitality venues without massively impractical increases in ventilation. Although there is a scientific consensus that ETS is a known cause of cancers, cardiovascular diseases, and respiratory diseases, although ETS contains 5 regulated hazardous air pollutants, 47 regulated hazardous wastes, 60 known or suspected carcinogens, and more than 100 chemical poisons, the tobacco industry denies the risks of exposure, opposes smoking bans, promotes ventilation as a panacea for ETS control, and works for a return to laissez-faire concerning smoking in the hospitality industry. Smoking bans remain the only viable control measure to ensure that workers and patrons of the hospitality industry are protected from exposure to the toxic wastes from tobacco combustion.


1) The "Proceedings of the Workshop on Ventilation Engineering Controls for Environmental Tobacco Smoke in the Hospitality Industry", sponsored by OSHA and the ACGIH concluded that presently available ventilation technology (well-mixed dilution ventilation) was unsatisfactory for controlling worker exposure to ETS. Air cleaning was similarly viewed as problematic. Of proposed technology, displacement ventilation was viewed as having the potential for 90% reductions in ETS levels, although the lack of performance data, the lack of familiarity of most ventilation engineers with the technology, and the difficulty in retrofitting existing installations poses major problems. Panelists viewed the lack of enforcement of ventilation rates by local building codes and the use of natural ventilation as further problems. Smoking seems to be declining among restaurant patrons.

2) In this report, I model ETS RSP and air nicotine levels for restaurants, bars, smoking lounges, bowling alleys and casinos to estimate hospitality workers' exposure to ETS. ETS RSP has been used as a non-specific tracer for ETS. Air nicotine and body fluid cotinine are the best and most widely used specific tracers for ETS. Using U.S. average smoking prevalence, ASHRAE Standard 62-1999 default occupancy levels, and recommended makeup air supply rates as ideals, shows for this ideal dilution ventilation, estimated ETS RSP levels will be between 100 and 200 g/m 3 , and air nicotine levels of from 10 to 20 g/m 3 . These predicted levels appear to be significantly lower than most observations, suggesting lower ventilation rates or higher smoker densities than expected. This is not surprising since neither smoker density nor ventilation rates are regulated.

3) Assuming ideal dilution ventilation, i.e., Reasonably Achievable Control Technology (RACT), estimated ETS risk levels for lung cancer and heart disease combined ranged from 15 to 25 per 1000 workers, which is 15 to 25 times OSHA's significant risk level, and 15,000 to 25,000 times the de minimis or "acceptable risk" level for federally regulated hazardous pollutants.

4) Assuming ideal displacement ventilation, i.e., Best Achievable Control Technology (BACT), estimated ETS risk levels for lung cancer and heart disease combined would be reduced by 90%, ranging from 1.5 to 2.5 per 1000 workers, to 1.5 to 2.5 times OSHA's significant risk level, and 1,500 to 2,500 times the de minimis or "acceptable risk" level for federally hazardous pollutants.

5) All cognizant health and scientific authorities in the U.S., including the US Environmental Protection Agency, the National Institute for Occupational Safety and Health, OSHA, the Surgeon General, the National Academy of Sciences, the National Cancer Institute, the National Toxicology Program andthe American Medical Association, have concluded that ETS exposure causes morbidity and mortality. The tobacco industry rejects this consensus.

6) Under Section 112 of the federal Clean Air Act, pollutants may be designated as "hazardous air pollutants" (HAPS) if they can cause serious morbidity or mortality, as ETS does. These ETS-like chemicals are regulated by NESHAPS which are far more stringent than either RACT or BACT. RACT and BACT are designed to control ordinary non-hazardous air pollutants. NESHAPS regulate HAPS to levels of de miminis risk with an adequate margin of safety. ETS contains 5 HAPS pollutants, more than 100 poisonous chemicals, and 47 chemicals classified as hazardous waste under RCRA. Although ETS qualifies, it remains unregulated as a HAP, as a poison, or as hazardous waste.

7) There are currently no official ETS indoor air quality (IAQ) standards in use in the U.S. Proposed NESHAPS-style ETS IAQ standards are based on limiting ETS lung cancer and

heart disease risk to de minimis levels. Application of these proposed standards to restaurants, bars, and casinos shows that tornado-like levels of ventilation would be required, 4 orders of magnitude (i.e. ten thousand fold) greater than possible by dilution ventilation, and 3 orders of magnitude (i.e., one thousand fold) greater than possible by displacement ventilation, with air cleaning intermediate.

8) Ventilation of buildings is a local government responsibility. Some building codes do not require that ventilation systems be operated after installation. Even under codes that require operation, ventilation standards are not enforced. Enforcement of ventilation standards, although desirable, would require establishment of new regulatory bureaucracies.

9) Enforcement of indoor air quality standards would also require additional new regulatory bureaucracy. Establishment of indoor air quality standards requires a high level of technical expertise, well beyond the capacity of most local government, and would be a years-long process (not including the resultant litigation, based on federal experience. It is doubtful that most jurisdictions would be willing or able to pay for these new regulatory regimes. Even if all the regulatory hurdles involving the setting of IAQ standards for ETS could be surmounted for lung cancer and heart disease, setting standards to protect against risks of ETS-induced breast cancer, stroke, SIDS, nasal sinus cancer, respiratory diseases, etc. would remain.

10) The tobacco industry's open and stated goal, currently available on their websites, is to actively promote ventilation technology as an optional control measure for ETS, at the option of hospitality business owners. The tobacco industry has made the hospitality industry a special target for ventilation technology. None of the "big three" tobacco companies concedes that ETS poses health risks to nonsmokers, and all promote "accommodation," a vaguely-defined code-word for letting the marketplace decide how to control ETS.

11) It is clear that smoking bans, such as in effect in the State of California represent the most cost-effective, easiest-to-enforce, and lowest risk alternative to ETS control. They appear profitable for business, and are also the only control measure known which is capable of yielding de miminis risk.