By Bob Baker

July 21, 22, and 23, a meeting was held in Research Triangle Park, North Carolina that will influence the direction of indoor air quality policy and science for years to come. The title of this conference was "Engineering Solutions to Indoor Air Quality Problems". The Air & Waste Management Association and the U.S. Environmental Protection Agency jointly sponsored it. The first meeting of this series was held two years ago and the next meeting will not be for another two years. The meeting was not large as conferences go with less than 100 persons in attendance. The meeting was however busy with 30 delivered papers and 32 additional discussed in the poster sessions over the two and one half days. In addition, the composition of both the audience and presenters was truly international with Asia, and Europe both well represented.

Policy and Research Direction

Although few in numbers, the attendance list at this conference could be used a virtual who's who of indoor air quality public policy and research direction. A majority of those present were either scientists from government or academia or government officials. There were a few professionals (either consultants or attorneys) and even fewer of us corporate based research types. Unlike most conferences that deal with practical application of IAQ principals and techniques, this one concentrated on basic research and future policy direction. To most, many of the sessions would be considered dry, if not outright confusing. A number of the papers were concerned with studies of the nature and size of contamination sources. These involved complex mathematical models and often-endless formulae and tables of experimental results. However, from this basic research, future techniques will either rise or fall.

Ions, Ozone and UV Light

Several technologies have been promoted to reduce indoor contamination and improve IAQ. The most widely promoted of these is Ozone, Negative Ion Generation and, more recently, Ultraviolet Light. Many devices utilizing one or more of these methods are marketed widely. Often, these products carry extravagant claims regarding their ability to kill bacteria and other organisms, eliminate VOC's and otherwise purify the air. Several of the papers reported on the efficacy and operational cost of such devices. A often cited problem with ozone is that it is harmful to health in concentrations over 0.5 parts per million. One claim made by some vendors of ozone generating equipment designed to be mounted in the ducts is that the ozone will eliminate contaminates in the ducts but, because it is unstable, will be absorbed or broken down before it can leave the duct and cause harm. Glenn Morrison of Lawrence Berkley Laboratory in California reported on a study that found that ozone is not absorbed or eliminated while passing through air ducts. In another presentation, Jianlei Niu from Hong Kong Polytechnic University reported on chamber tests of 26 commercially available ion and ozone generators. He observed that all units tested gave off high levels of ozone. The concentrations he reported were above what is generally considered a safe level. T. K. Goswami of Universal Air Cleaning presented a paper, which reported a high level of effectiveness for a Photocatalytic (UV Light) system for cleaning air. Lisa Stevens from the University of Colorado reported studies with several Photocatalytic designs that suggested that they were of limited effectiveness in removing some compounds. Bruce Henschel of the U.S. EPA reported on a study of the cost of utilizing Photocatalytic systems to remove contamination. His analysis found that they are ten times more expensive to install and twice as expensive to operate as other approaches. In addition, he suggested that an adequate system might require more space than all other components of the HVAC system together. Based on the evidence presented at this conference, ozone and negative ion generation do not look like viable contamination control methods. At best, Photocatalytic Oxidation needs a lot more study before the claims that are being made can be verified.

Improved Filtration Works

Barney Burroughs (A past president of ASHRAE) of the IAQ/Building Wellness Consultancy reported on some very interesting research comparing the effectiveness of no filtration, low efficiency (standard fiberglass throw away) filters, medium efficiency filters (mini pleats) and higher efficiency (deep pleats) filters. The study was especially interesting in that it was conducted in normal residences in the Atlanta area with usual household activities rather than in the usual laboratory setting. It was notable that accurate particle measurements showed that results in the home closely matched laboratory results utilizing the new ASHRAE 52.2 test standard. This suggests that the new test method is a good predictor of filtration efficiency in actual use. The study also confirmed the value in terms of improved air quality of using high efficiency filtration. Particulate levels in the homes when using medium and high efficiency filtration were significantly lowered. There was little difference between the low efficiency filters and no filtration at all.

ASHRAE Standard 62 takes a new turn

Barney also clarified actions taken by the ASHRAE board at the end of the June meeting in Boston. They have placed the present Standard 62 under the ANSI "continuous maintenance" process. This means that rather than the new 62R draft which we have discussed previously taking effect, a series of potentially smaller changes will be made to Standard 62-89. In addition, they decided that 62-89 will apply to commercial facilities and a new standard will be prepared that will apply to residences. This move will have a huge impact on contractors who specialize in residential systems or who have a major portion of their business in residential work. So you will more fully understand the impact of these decisions, we will discuss in future issues both Standard 62-89 and chapter 9 from the 62R draft. This chapter is titled "Requirements for Residential Buildings" and may well set the pattern for the new standard. At a minimum, many of its ideas will be considered in preparing the new standard. In the coming months, a committee will be appointed to deal with the new residential standard. We will keep you up to date on these developments. In the next issue, we will complete our coverage of the conference by discussing some research findings dealing with bacterial and fungal growth in air ducts and other parts of the system.

Mr. Baker's field of expertise is the control of contamination in air-conditioning and ventilating systems by mold, mildew and bacteria. He writes and speaks frequently about the efficacy, legal risks, and regulatory issues involved in various control strategies. He serves on ASHRAE Technical Committee TC 2.3, TC 2.4, TC 9.8, and Sampling of Airborne Particulate Concentration in Commercial and Residential Buildings GPC 17P. He also serves as a member of ASTM D22.06 (Indoor Air Quality) and is on the Board of Directors of the Indoor Air Quality Association and the Florida Public Health Foundation. Because HVAC applications encompass new uses from an U.S. EPA regulatory standpoint, Mr. Baker works closely with the EPA and industry groups, including serving as the chair of the IAQ committee of the Consumer Specialty Products Association, to help formulate policy in this area.

Bob Baker is Chairman and CEO of BBJ Environmental Solutions, Inc., a company specializing in providing clean air through environmentally responsible products, such as BBJ MicroBiocide , BBJ Micro Coil Clean , "FreshDuct Odor Eliminator ", and BBJ Mold and Mildew Remover™ as well as the revolutionary new Power Coil Clean™. For additional information, Mr. Baker can be reached at (800) 889-2251 or through the company web site at http://www.bbjenviro.com.