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The purpose of this paper is to propose a screening test for indoor air quality (IAQ) assessment by auditing only a few “dominant” contributors for preliminary measurements in air‐conditioned offices.

In Hong Kong, up to ten common indoor air pollutants have to be audited in determining the IAQ acceptance for typical air‐conditioned offices. Indeed, parameters could not be uniformly contributed to the assessed “IAQ satisfaction”. The study reviews the past ten‐year assessment experiences in Hong Kong and investigates the “dominant” contributors of unsatisfactory IAQ for screening tests.

When compared with the “full” assessment of all ten listed parameters, a screening test with assessment parameters reduced by half would correctly identify 96 per cent unsatisfactory and 95 per cent satisfactory cases.

The screening test was developed with the reported patterns of the ten common air pollutants from on‐site measurements and survey studies in typical air‐conditioned offices in Hong Kong. Therefore, the test application may require adaptation for use in other countries.

The study shows the usefulness of a regional database in developing a screening strategy for IAQ and so it would be a useful reference for policymakers in evaluating a cost‐justified IAQ assessment protocol.

The paper proposes a simple screening test which can identify the probable unsatisfactory IAQ in offices by assessing only a few “dominant” contributors, with selection of representative assessment parameters based on experiences.

The applications of gas chromatography in studies of air pollution have been reviewed by Braman (28) who stated that most substances in the environment could be examined chromatographically by following suitable sampling procedures. In particular mention was made of the analysis of permanent gases and vapours, locally‐high concentrations of chemicals such as may be found in the region of manufacturing plants, and the examination of particulate matter subsequent upon the use of appropriate collection techniques. Three methods for the collection of air samples were described.

The City of New York was suddenly and deliberately attacked on September 11, 2001, killing thousands of people and leaving unbelievable destruction. Thirty-eight buildings and structures were destroyed or damaged, including seven buildings in the World Trade Center site completely leveled. Almost five years later, two very large contaminated buildings, Deutsche Bank at 130 Liberty Street and Fiterman Hall of Borough of Manhattan Community College, have yet to be cleaned up and demolished. Some 30 million square feet of commercial space was lost. Transportation was disrupted, including the loss of the World Trade Center PATH station, the 1/9 subway line and portions of Route 9A and Church Street. Cars were not allowed south of Canal Street for a week. For Americans this was a terrorist attack and a crime. It was a time for mourning losses and responding to disaster. There was the shock that something like this could happen. And there was more. The destruction of the WTC also posed competing environmental, economic and social threats.

The purpose of this paper is to present a new technique for monitoring gas leakage in underground pipelines to prevent dangerous explosions.

A novel system for monitoring methane concentration in underground spaces was developed by integrating the multi-channeled air sampling method with an infrared gas sensor. A pipe installation methodology (without excavation) was established and verified accordingly.

The proposed approach was proven successful in reducing the quantity of sensors needed for real-time monitoring of underground pipeline leakage by about 80 per cent. Furthermore, this system lowers total operational cost by as much as 60 per cent.

The results presented here represent a possible solution to reducing the public safety risks associated with explosions and fires caused by pipeline leakage in underground spaces. Its total cost is low and its monitoring efficiency is high.

The purpose of this paper is to explore inhalation levels and dermal exposure to toluene among printing workers who wore no personal protective equipment; it is conducted in a plastic bag factory. Using a charcoal cloth pad (CCP) as a dermal sampler to assess skin permeation of liquid toluene is also investigated.

In total, 27 stationary air samples as well as urine and dermal samples were collected over 9 days from 11 printing workers. Six pieces of CCP were wrapped on each of the workers’ fingers for the dermal sample collection. Air samples were collected and analyzed according to NIOSH No. 1501, and 65 post-shift urine samples were collected and analyzed using gas chromatography equipped with headspace sampler (GC-HS/FID). Multiple linear regression was employed to analyze the association between the studied variables.

The mean (SD) urinary toluene (UTol) level was 13.42 (9.72) ug/L. Toluene on the CCP (TolCCP) was a meaningful predictor for UTol (p-value=0.027) with r and r² values of 0.441 and 0.195, respectively. The r and r² of the model using the toluene time-weighted average concentrations in air were 0.739 and 0.546, respectively. The absorbed dose of toluene determined from the TolCCP ranged from 1.05 to 91.94 mg, accounting for 12.3 percent of the threshold limit value (TLV).

Dermal exposure was insignificant when workers wore respirators, but when not, dermal absorption could contribute to the overall uptake and exposure above the TLV. Appropriate gloves should be assigned to the workers to reduce dermal exposure to toluene.

This paper aims to present the most influential factors on classroom indoor PM_2.5 (Particulate Matter < 2.5 µ), determining the level of PM_2.5 concentration in five pre-schools located in the most densely populated district of the Tehran metropolitan area (district 6) as a case study to consider the children's exposure to air pollutants and introducing a suitable model, for the first time, to predict PM_2.5 concentration changes, inside pre-schools.

Indoor and outdoor classes PM_2.5 concentrations were measured using two DUSTTRAK direct-reading instruments. Additional class status information was also recorded; concurrently, urban PM_2.5 concentrations and meteorological data were obtained from the fixed monitoring stations and Meteorological Organization. Then, the predicted concentrations of the indoor PM_2.5, from introduced multiple linear regression model via SPSS, compared with the nearest urban air pollution monitoring stations data.

The average outdoor PM_2.5 concentration (43 ± 0.32 µg m⁻³) was higher than the mean indoor (32 ± 0. 21 µg m⁻³), and both were significantly (p < 0.001) surpassing the 24-h EPA standard level. The indoor PM_2.5 concentrations had the highest level in the autumn (48.7 µg m⁻³) and significantly correlated with the outdoor PM_2.5 (r = 0.94, p < 0.001), the number of pupils, ambient temperature, wind speed, wind direction and open area of the doors and windows (p < 0.001). These parameters, as the main determinants, have led to present a 7-variable regression model, with R² = 0.705, which can predict PM_2.5 concentrations in the pre-school classes with more than 80% accuracy. It can be presumed that the penetration of outdoor PM_2.5 was the main source of indoor PM_2.5 concentrations.

This study faced several limitations, such as accessibility to classrooms, and limitations in technicians' numbers, leading to researchers monitoring indoor and outdoor PM concentrations in schools once a week. Additionally, regarding logistical limitations to using monitoring instruments in pre-schools simultaneously, correction factors by running the instruments were applied to obtain comparable measurements.

The author hereby declares that this submission is his own work and to the best of its knowledge it contains no materials previously published or written by another person.

Presents the principles of analytical methods, environmental monitoring, biological monitoring and direct human exposure assessment of lead and cadmium. Illustrates each research area, by giving the results obtained from studies carried out in the Croatian region and performed within the Institute of Medical Research and Occupational Health in Zagreb. Also presents the results obtained for lead and cadmium in non‐polluted rural, urban and polluted industrial areas. Considers two main environmental media ‐ air and food ‐ when evaluating human exposure, intake and absorption of lead and cadmium. Compares results obtained in this region to reported European and global data.

I By adding an impaction plate in a graphite furnace it is possible to separate and collect 6µm particles which are found in cigarette smoke. This allows for the quantitative detection of Cd, Cr, Pb and Mn in air in a direct fashion and quasi real time. It is important to monitor not only direct inhalation of cigarette smoke, but also “second‐hand” smoking by innocent by‐standers.

Reducing Level of Alcohol in Inks ‐ A medium‐sized US ink manufacturer recently needed to reduce the level of alcohol in its bases for water‐based inks. Ciba Geigy Pigments Division's Inks Technical Centre developed an improved formulation, containing half the alcohol of the previous one and 40 per cent more pigment to allow the ink producer to meet VOC limits and increase production efficiency, at no additional cost.