sample="quota" bates="2023295614" isource="pm" decade="1990" class="ni" date="19940225" FEB-25-94 FRI 10:07 HBI . USA P.02 HBI-USA 10378 Democracy Lane Fairfax, Virginia 22030 (703) 352-0102 (703) 352-0151 (fax) HBI Healthy Buildings International MEMORANDUM TO: David Laufer, Cappie Alverson, Mary Pottorff -- Philip Morris Kathy, Yoe, Walter Woodson -- Tobacco Institute John Rupp -- Covington & Burling John Jewell -- California Business and Restaurant Alliance FROM: Gray Robertson DATE: February 25, 1994 SUBJECT: Ventilation in Restaurants and the Hospitality Industry Within the last few weeks, I've been asked by several sources about ventilation requirements in restaurants, hotels, casinos, etc. The issue that precipitates all these requests is how can existing restaurants accommodate the ASHRAE 62-1989 "Ventilation for Acceptable Air Quality" standards. As we all have long realized, the ASHRAE standards tend to be the foundation on which most building codes are based for ventilation rates. Furthermore, since minimum ventilation rates for offices in the 62-1989 standards moved from 5 cfm per person to 20 cfm per person, two major concerns about existing buildings were: 1 Could the existing ventilation system deliver the extra air? 2 Wouldn't a fourfold increase in ventilation rate lead to a fourfold increase in operating costs? Let us first understand why most of these fears are groundless in offices and then look at the real situation in restaurants. I see nothing but good news for the hospitality industry! 1 Can the existing ventilation system handle the extra air volume? Consider a typical ventilation system for an office housing say 100 people. Pre-ASHRAE Std 62-1989 Outside air minimum would have been 5 cfm x 100=500 cfm Post-ASHRAE Std 62-1989 Outside air minimum would be 20 cfm x 100=2000 cfm However, this is only the outside air fraction. The volume of supply air (supply air = total of outside air + return air) would typically have been 9000 cfm. It would take 9000 cfm of supply air at the correct supply air temperature to provide cooling for the 100 people at the design load condition, i.e., the ventilation system must have been sized for handling 9000 cfm. The fans and ductwork have the capacity to handle 9000 cfm. Thus, changing from 500 to 2000 cfm of outside air simply changes the percent of outdoor air in the supply air from 5.6% to 22%. The ventilation system fans and ductwork etc. still move around the same volume of total air. The only limiting factor is whether or not the existing chill coils have the capacity to cope with the extra percentage of outdoor air. In most office environments, the coils can accommodate the change for most of the year. Perhaps in extremes of temperature we can have undercapacity, but this does not apply to most restaurants (see below). 2 Will a fourfold increase in minimum ventilation rates mean a fourfold increase in costs? This is partly answered in prior explaination. We do not increase the total ventilation air four-fold. We only change the outside air content from 5.6% to 22%. Understanding this basic fact can help us appreciate why every credible study made to date shows that the real cost increase from switching from 5 to 20 cfm minimum outdoor air raises ventilation costs by no more than 5-10% total. Again, even this does not apply in most restaurants. Restaurants and the Hospitality Industry If we compare the minimum outdoor air ventilation rates for areas relevant to this industry between old ASHRAE standards and new or current standards, here is what we see: Observations 1) Any restaurant, hotel, ballroom, bowling alley, etc. that allowed smoking in the past built or remodeled sine 1981 and meeting the then current ASHRAE standards has more ventilation capacity than ASHRAE 62-1989 requirements. 2) Any bar, cafeteria, hotel conference and/or assembly room built between 1973 and 1981 meeting the then current ASHRAE standard has as much or more ventilation capacity than ASHRAE 62-1989 requirements. 3) Only the following areas built between 1973 and 1981 that applied the then current ASHRAE standards may have difficulty meeting 62-1989 levels: Dining rooms built between 1973 and 1981 Hotel lobbies built between 1973 and 1981 Bowling alleys and ballrooms built between 1973 and 1981 However, there would only be a problem if the then minimum ventilation rates were used. If the recommended rates were chosen, every facility that ever allowed smoking in the past has the installed capacity to meet ASHRAE 62-1989 today. 4) Offices In the past, we have all been concerned for too long with the burden existing offices have in complying with ASHRAE 62-1989. Everyone automatically presumed major ventilation upgrades despite the fact that HBI research showed most offices, new and old, could accommodate moderate smoking if operate correctly. Now we see clearly why and how this is: a) Any office built between 1973 and 1981 that used minimum ventilation rates had 15 cfm/person of outdoor air. If they used recommended rates, they had 15-25 cfm/person and therefore even exceeded ASHRAE 62-1989. b) Any office built between 1981 and 1989 that assumed some degree of smoking should have specified the 20 cfm ventilation rate, not the 5 cfm figure assumed by many, i.e., the vast majority of existing offices did have designs meeting ASHRAE 62-1989 standards. Recommendation In view of this review, every hotel, restaurant, bowling alley or their respective hospitality associations when informed on these issues should willingly embrace ASHRAE 62-1989 and help its adoption at every city, state and national level. Gray Robertson GR:dh