Indoor Air Pollution

Radon, Bioaerosols, and VOCs

Jack G. Kay, George E. Keller, Jay F. Miller

• Publisher: CRC Press
• Year: 2021
• eBook ISBN: 9781000448108
• Topic: Technology & Engineering
• Subtopic: Chemical & Biochemical Engineering
• Index: Technology & Engineering

Indoor Air Pollution: Radon, Bioaerosols, and VOCs covers the most current aspects of indoor pollution research, including vitally important topics such as radon, bioaerosols, and volatile organic compounds. The book presents information on microbial contamination abatement, chemical characterization of air samples, sick building syndrome, biological pollutants, liability of indoor air pollution, and measurement and control of radon. Industrial hygienists, toxicologists, safety officers, and engineers in industry and academia should consider this book a "must read" selection.

Part I

CHAPTER 1

Overview of the ACS Symposium on Indoor Air Pollution^*

J.F. Miller and G.E. Keller

Over the past few years public interest in indoor air pollution has grown considerably. A large part of this interest began when Legionnaire’s disease was discovered in 1977, but the roots of indoor air pollution probably go back to World War II, when energy conservation started, or before. One could argue that the first indoor air pollution problems occurred when man brought fire inside a cave. However, the energy crisis of 1973 certainly exacerbated today’s indoor pollution problems. At that time the country began looking for ways to conserve energy. Since the largest user of energy in the country is the building sector, when energy needed to be conserved, that was one of the primary targets. Buildings use even more energy than transportation, consuming 40% of the total energy budget. In order to conserve energy, two types of changes were made. The first was to make the equipment used in buildings more efficient. A modem refrigerator is a considerable improvement over one made 15 years ago. What this means is that if the 125 million refrigerators and freezers now operating in this country were as inefficient as those of 15 years ago, then 20 1000-megawatt power plants would have to be built just to furnish the extra energy. Energy savings allowed by better design of equipment has no repercussions. All the savings have been obtained quite inexpensively.

However, a second type of energy savings was to insulate buildings, stop air leaks, and use as little outside air as possible. This behavior has also saved great amounts of energy, though at a cost. This cost results from not enough outside air entering a building to sweep out pollutants that are generated within the building. Furthermore, pollutants brought in from the outdoors add to those generated inside. Thus, indoor levels of air pollution may be considerably worse than outdoor levels. Indoor air pollution has been termed “the worst health problem in the U.S. accounting for 50% of all illnesses.”² The cost of the illnesses is staggering, but we cannot turn back energy conservation. If we used as much energy per capita as we did in 1973, we would need 35% more fuel. This is about one half the entire production capacity of OPEC. So, what needs to be done is determine ways in which these great energy savings can be accomplished, while providing clean indoor air.

In order to accomplish such a lofty goal, we must understand what indoor air pollution is and what are its causes. In newspapers, magazines, television, and radio, one is exposed to stories of polluted indoor air. The stories are often just that: stories, bits and pieces of information thrown at the public. Furthermore, in some states the legislators have started acting on these stories. Unfortunately, actions are being taken before it is really known what actions to take, which may be unwise. Consequently, the ACS Symposium was held to investigate questions such as:

• Can we measure biological contamination accurately?

• Can we abate/contain biological contamination?

• Is it possible to stop biological growth by the proper use of bactericides?

• Can we measure volatile organic compounds (VOCs), as well as nonvolatiles, in the air at the low levels typically found in indoor environments?

• What levels of VOCs are acceptable?

• What health risks are associated with low levels of VOCs?

• Are there methods to minimize VOC content in the air?

• Will increasing air intake alleviate indoor air pollution?

• What happens when the outdoor air is polluted?

• Will building bake-out elute VOCs from a building?

• Is building bake-out really a good idea, or is article bake-out prior to installation in the building a better idea?

• What types of air cleaners will give clean indoor air?

• How well will these air cleaners work?

This list does not include radon issues, which is covered in a separate section of the proceedings.

The symposium also investigated reasons that indoor air pollution has obtained national recognition. One driving force is the threat of lawsuits. Lawsuits may be directed at any person involved with the design, construction, maintenance, and ownership of the building. The primary reason for the broad range of defendants is that the causal relationships between indoor air pollutants and human health are not well known. Furthermore, standard techniques for measuring air quality are not well defined. The first article of the proceedings discusses the influence of legal issues in the development of concern for indoor air.

The next portion of the proceedings deals with biological pollution. Different sampling techniques are discussed. Most of the more established sampling methods involve growing samples of microorganisms obtained from the air on nonspecific agar. This sample must be subcultivated so that the species of organisms can be identified. Identification protocols are very time consuming and only a highly trained microbiologist can perform them. Species identification may be quite important because the degree of human response varies over a wide range, depending on the organism. For example, one tuberculosis organism can infect a healthy person, while it usually takes about one million Legionella pneumophila organisms to infect a healthy person. Also, some organisms, e.g., Aspergillus niger, are not usually pathogenic, but can induce allergenic responses in people. Furthermore, organisms like A. niger can become pathogenic under certain circumstances. Hence, it is difficult to quickly ascertain whether biological contamination of indoor air may be a cause of indoor air pollution in a particular building.

One quite interesting new assay is an enzyme-linked immunoassay (ELISA) test for L. pneumophila. The primary advantage over normal sampling techniques is that the test determines the presence of Legionella sp. Furthermore, this test is quite rapid and does not have to involve a trained microbiologist.

The minimization of biological aerosols by two quite different techniques is discussed in two papers. In the first case, the causal age...

Table of contents

• Cover
• Title Page
• Copyright Page
• Preface
• Table of Contents
• Part I
• Part II
• Appendix
• Index