Saturday, March 15, 2008

Smoke-Free St. Louis City gets ventilation wrong.

The latest post on the Smoke-Free St. Louis City website claims that ventilation and air filtration won't protect bartenders from cigarette smoke since "ventilation cannot purify the air at rates fast enough to protect people from secondhand smoke exposure."

Yet ASHRAE and OSHA allow ventilation and air filtration to protect workers in enclosed parking garages and welding shops from far more deadly smoke and fumes.
http://www.garasjeventilasjon.no/lager/Ventilation%20for%20enclosed%20parking%20garages.pdf
http://www.engwald.com/pdf/weld_page1.pdf
http://www.air-quality-eng.com/welding.php
http://cleanairquality.blogspot.com/2005/10/secondhand-smoke-in-bars-restaurants.html

A study by the Oak Ridge National Laboratory found that restaurant ventilation/filtration systems can make the air of a nonsmoking section ofa smoking restaurant as clean as the air of smoke-free restaurant.
http://www.data-yard.net/2/21/rtp.pdf

The CDC even recommends that such air filtration systems be installed inbuildings as a way of protecting workers from airborne chemical, biological or radiological attacks:
http://www.cdc.gov/niosh/docs/2003-136/

So why is tobacco smoke being single out as the one workplace airborne hazard that ventilation and air filtration can't handle?

The Smoke-Free St. Louis City site correct quotes an official ASHRAE statement that claims no technology exists which can perfectly prevent the exposure to tobacco smoke in a space in which smoking is allowed and therefore such ventilation and air filtration technology cannot be considered adequate health protection against indoor tobacco smoke.

"At present, the only means of effectively eliminating health risks associated with indoor exposure is to ban smoking activity... No other engineering approaches, including current and advanced dilution ventilation or air cleaning technologies, have demonstrated or should be relied upon to control health risks from ETS [environmental tobacco smoke] exposure in spaces where smoking occurs."

It should be noted that a large portion of the ASHRAE engineers objected to and fought the adoption of this statement. And all the local ventilation engineers I talked to for the St. Louis County Council believed well-designed ventilation systems could safely allow smoking in St. Louis bars and restaurants. But I will concede, no system is perfect. Yet no one disagrees ventilation and air filtration machines can hugely reduce the smoke in any venue that allows smoking. Whether tiny residual exposures to tobacco molecules still constitute a real health risk is hugely controversial. In a free society, people over 21 should be allowed to take such minute "risks" concerning which they have been overwhelmingly warned.