Indoor Air Quality - Essay Example

Annotated Bibliography Annie Chatfield Corsi, Richard L. (Sept. 2000). "Indoor Air Quality: A Time for Recognition. Air and Waste ManagementAssociation, 10-14. This article discusses about the issues that lead to poor indoor air quality. Some typical examples in this regard are homes being built with attached garages. These garages sometimes contain residues from automobile exhaust as also other consumer products' fumes (products present in the garage that contain evaporants) that can enter the home and cause harm if they go unnoticed. Some consumer products such as cleaning products and aromatic candles that are normally found within the house and also contribute towards such pollution of the air have also been discussed. Other indoor contaminants that have been discussed in detail are the usual ones such as gas stoves and building materials. The article also highlights the fact that modern facilities such as air conditioning and weather proofing helps retain the contaminants indoors. In this regard, Corsi points out that Americans spend nearly 87-90% of their time indoors, making indoor air quality an important topic that needs to be researched. It has been noted that some of the common contaminants include CO, NOx, and VOC's (volatile organic compounds). One VOC, formaldehyde has been found to be emitted from panel board and furniture. Other sources of VOC's are computers and laser printers. Radon, a carcinogen, is also a matter of concern when it comes to good indoor air quality. This is because drinking water may be one entry point for radon to the home along with other products as a result of the chlorination of water. In this article, Corsi has pointed that whenever the issue of air quality is discussed, importance is given usually towards outdoor air quality, whereas indoor air quality is often neglected. Likewise, when it comes to funding any study or research on air quality, it is usually out door air quality that is considered as the judging criterion, while indoor air quality is totally neglected. This article therefore, highlights the need for extensive research and funding for studying indoor air quality as well as stresses on the need to educate the public on its importance. 2. Corsi, R.L., Siegel, J., Karamalegos, A., Simon, H. & Morrison, G.C. Personal Reactive Clouds: Introducing the Concept of Near Head Chemistry. The authors in this article study the chemical reactions that occur around the head when colognes or perfumes are used. The study is aimed at studying the reactions of ozone with terpenes and terpenoids that are known to cause elevated particle concentration within the body of the wearer. Such increase in the levels of these substances can give the wearer respiratory symptoms or eye reactions. Linalool is one of the common terpenoids and is used in many products. The oxidation of Linalool yields one product called methyl-5-vinyl-terahydrofuran-2-ol (MVT). For studying these reactions and their resulting impact, the time that the air remained near the perfume wearer's head was measured based on the dimensions of the head and the air speed. The procedure included a stainless steel chamber placed over the head of the human subjects. A flow of air was generated which passed from one side of the subjects head to the other. The ozone present was measured with the help of a UV-absorbance ozone detector. Air was tested before and then tested again after subject was placed in the chamber. The subject applied the personal care product as part of test and samples were taken again 20-30 minutes after the product was applied. Particle measurements were determined due to the reaction of ozone and the chemicals in the personal care products. The study found that there was a substantial increase in the concentrations of the fine particles, and the statistical results showed that they were more than the permissible levels. However, a detailed research has been recommended in studying the chemical reactions that take place near the head during the application of many different personal products. 3. Hubbard, H.F., Coleman, B.K., Sarwar, G., & Corsi, R. L. (2005). Effects of an Ozone-Generating air purifier on indoor secondary particles in three residential dwellings. Indoor Air, 15, 432-444 Although there have been laboratory studies undertaken for determining the effects of air purifiers and number of particles as also the sizes of such particles, such studies have only been conducted within a laboratory setting. This study described within this article has researched on ozone generating air purifiers and the use of terpenes and their effect on particle size and numbers in three residential dwellings. As part of this research, ozone generators were initially used without terpenes and then along with a common terpene called limonene that evaporates into the air. The terpene, limonene evaporated into the air and was picked up by the ozone particles, which eventually resulted in an increase in the number of particles (esp. fine particles) in all three dwellings. It was also found that the smaller particles had increased in diameter (less than 0.7 um). The particles detected were confirmed as pollutants that are known to affect people who are prone to respiratory problems and affects the young and old population without any distinction. 4. Morrison, Glen & Corsi, Richard L. (May, 2003). Smog and Lemons - Discovering Indoor Air Chemistry. Journal Air and Waste Management Association, 14-20. Morrison and Corsi state through this article that the exposure of indoor air pollutants is greater than outdoor air pollutants amongst us. One reason for this can be attributed to the amount of time Americans spend indoors. This merits the new term Sick Building Syndrome (SBS) that causes itchy eyes, nose and throat. The air present indoors traps pollutants inside the walls of the building and is this rate of trapping is enhanced by poor building ventilation. The ozone formed outdoors enters into the home through doors, windows and the ventilation system. Ozone can also be released from technology such as laser printers and air fresheners that are used to rid homes of dust and mold. Another major area of this study is terpenes that are natural organic chemicals found in cleaning substances. Terpenes react with the ozone present in the air to form byproducts which are harmful. According to a Harvard study, an increase in small particle concentrations were found to be harmful and were found to increase mortality. Also, chemical reactions with ozone produce products that increase irritation of the nose and eyes much more than the effect of the reactants. Terpenes and ozone produce carboxylic acids and aldehydes, which are eye and nose irritants. Lemonene, a natural terpene, is used frequently as a lemon scent in cleaning products and is very reactive. It has been recommended to avoid this terpene. Of course, avoiding ozone indoors is a must. One measure to counter the stagnation of indoor air is to open windows in the evening that would help decrease the amount of ozone within the home. However, much research is needed in the area of indoor air quality for studying its effect on different substances such as carpet and wall paint. 5. Poppendieck, D., Hubbard, H., Ward, M., Weschler, C., & Corsi, R. L. Ozone Reactions with Indoor Materials during Building Disinfection. The purpose of this study was to look at the effects of high concentrations of ozone for use as a disinfectant on different building materials. The method of study used in this regard was to expose twenty four materials to ozone and evaluate its effect on these materials. As a result of the reaction of ozone with these building materials, by-products such as aldehydes and ketones were formed. The research study was in fact, done in steps. The first step was to take measurement before the introduction of ozone and lasted for nine hours. The second stage was the disinfection stage lasting 16 hours where around 1000 to 1200 ppm of ozone was injected continuously into the experimental system. The third step was the disinfection stage under which data was collected for 20 hour duration. The by-products evolved were collected and analyzed during each stage. As many as fifteen chemicals were measured and found to be belonging to the C1-C9 class of saturated n-aldehydes and ketones. Data obtained was analyzed for ozone deposition velocity and reaction probabilities for test materials and BDBP mass releases per unit material over the disinfection and post disinfection periods were calculated. Materials that had the highest deposition velocities were ceiling tile, office partition, fiberboard (medium density) and gypsum wall backing. The total by product release rates calculated over a period of 36 hours were found to be statistically high for paper, office partition and fiber board (medium density). These materials were further noted to be high in commercial buildings and further research should be done. 6. Sarwar, Golam, Olson, David A., Corsi, Richard L. & Weschler, Charles J. (2004). Indoor Fine Particles: The Role of Terpene Emissions from Consumer Products. Journal of Air and Waste Management Association, 54, 367-377. The purpose of this study is to look at consumer products with terpenes and how they react with ozone to form secondary organic aerosol growth. This experiment evaluates five consumer products with low or high presence of ozone and its effect on numbers of fine particles. The experiments were conducted in a stainless steel chamber to duplicate indoor air in the laboratory setting. Ozone was placed in the chamber and then one of the consumer products was added in recorded amounts. Particle counters were used to count the number of fine particles in the chamber. The results for each experiment stated above are stated here. High concentrations of ozone within each of the five consumer products produced a significant increase in the number of fine particles that ranged from 211,000 no. /cm3 in general purpose cleaners to 670,000 No./cm3 in liquid and solid air fresheners and wood floor cleaners. The five consumer products, under the presence of low concentrations of ozone showed varying results from almost no increase for solid air fresheners to a significant increase for liquid air fresheners. The perfume and floor cleaner fell in between these listed results. This study has shown the need for less indoor ozone by preventing the ozone outside from getting in and by avoiding the use of air purifiers at home. The study further shows that the use of non-terpene based cleaners and air fresheners indoors was recommended. 7. Sarwar, Goalm, Corsi, Richard, Allen, David, & Weschler, Charles. (2003). the significance of secondary organic aerosol formation and growth in buildings: experimental and computational evidence. Atmospheric Environment, 37, 1365-1381. Under the study, two methods were used for the purpose of collecting data. One was an experimental set up of a model used for the assessment of indoor air quality. Under this, a chamber was used that simulated the surface to volume ratio of some commercial and residential buildings. Particle numbers and size were measured. Additionally, the mass concentration was measured using particle number concentration and particle density. The other method called ICEM (Indoor chemistry and Exposure Model) was a mathematical model used for predicting the particle mass concentrations. Experiments were conducted to study the particles formed from the homogeneous reaction of ozone and -pinene. The reaction mechanisms of this reaction were reviewed with its effect on indoor particles, as a result of which, six semi-volatile compounds were found that included aldehydes and acids. The range and concentration of the particle sizes were measured using the LASAIR particle counter, which predicted that the indoor particle mass concentrations were similar to that obtained from the experimental data. The authors say this may due to the increased understanding of particle formation and particle growth processes. The experimental data showed an increase in the rare of particle formation indoors that was characterized by conditions such as low air exchange rates, lower indoor air temperatures, higher outdoor particle concentrations or higher indoor -pinene concentrations. Thereafter, it was recommended that indoor air purifiers should not be used due to the detection of an increase in potentially harmful substances such as aldehydes, organic acids and fine particles. Read More