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A pilot project was conducted to determine the effect of common construction dusts as interferences in a new portable end-of-shift (EoS), direct-on-filter (DoF) sampling and analysis method for respirable crystalline silica (RCS), in this case, quartz. Construction dusts were prepared from plaster, drywall, cement and brick by grinding, aerosolizing, and collecting respirable dust with high flow rate cyclones. Filters were loaded with different levels of commercial α-quartz powder Min-u-Sil 5, and different levels of interfering dusts, singly and in combination. Samples were analyzed by Fourier Transform Infrared Spectroscopy (FTIR). Good correlations were found between nominal quartz loading (0 µg, 25 µg, 50 µg, and 100 µg) adjusted for quartz in the interfering dust and FTIR absorbance alone and in the presence of all interfering dusts. The slopes of the correlations were similar whether the loading was quartz without interference, or with plaster, drywall, and cement dusts, regardless of quantity. The results show that (a) plaster and drywall dusts do not interfere substantially; (b) cement does not interfere, but a change in the intercept suggests an effect on the background absorbance of the filter; and (c) in addition to having a substantial quartz content, brick dust contains an additional material, probably a silicate mineral, which interferes with the quartz peak. Thus, the presence of cement leads to lower quartz values and brick leads to higher values, but overall, 83% of the quartz contents predicted from the calibration data agreed within 50% of the adjusted nominal loadings within the range 20-110 µg. This result is encouraging given the high levels of interfering dusts. Nine samples loaded with smaller amounts of all four dusts together gave results within 25% of the adjusted nominal loadings. A single mixture addition of the dusts to the filter gave tighter variance in results than sequential additions. Unexpectedly, the two Certified Reference Materials (CRMs) 1878a and 1878b, gave different results when used to calibrate XRD analysis of Min-u-Sil 5.

Impregnated filters treated with alkali and humectant were first used as collection media to assess occupational exposure to sulfur dioxide (SO2), as outlined in the National Institute for Occupational Safety and Health Method 6004 in 1979. Since then, updated treatment protocols have been proposed with decreased amounts of alkali and glycerol, which claim the same filtering capacity. However, there has been no report on how the collection of SO2 on such impregnated media is influenced by relative humidity (RH). This study investigated the role of glycerol (G) amount on impregnated filters (G2 and G10, referring to 2 and 10% glycerol, respectively) in the collection of SO2 (100 l of 10 ppm at 1 l per minute) under low, medium, and high RHs. The testing results show that RH significantly impacted G2 filters with respect to breakthrough time, capacity, and recovery. At low RH, the 5% breakthrough time was less than 10 min and its recovery was merely 42%; at medium and high RHs, although the recovery was satisfactory, the 5% breakthrough time was still less than 100 min. By contrast, G10 filters illustrated nearly 100% recovery and evaluation by analysis of variance showed no significant effect of RH on recovery. In summary, the current treatment protocol of 2% glycerol leads to a significant underestimation of the exposure to SO2 in a low-RH environment; increasing the glycerol content can be an effective alternative to compensating for the effect of RH., (© The Author(s) 2019. Published by Oxford University Press on behalf of the British Occupational Hygiene Society.)

Background: There is little research exploring training effects of engaging in active video gaming activities., Objectives: This study sought to determine the cardiovascular and metabolic responses, changes in flexibility and exercise adherence to an aerobic dance exercise programme using the XBOX Kinect over a 6 week training period., Methods: Training was conducted using the Just Dance 4 disc on the XBOX Kinect 360. Participants attended five, 30 minute sessions per week for the first two weeks, four 45 minute sessions per week for the next two weeks and three 60 minute sessions per week for the last two weeks. Outcomes assessed included flexibility, body mass index (BMI), percentage body fat, maximal oxygen consumption (VO2max), resting and post exercise blood pressure, heart rate and blood lactate levels., Results: There were significant improvements in flexibility, maximal oxygen consumption and resting heart rate. There were no significant changes in BMI, percentage body fat or blood lactate levels. Nine (37.5%) participants continued to engage in this form of exercise at least 3-days per week over the 3-month post intervention follow-up period., Conclusion: Engaging in dancing using dance videogames can lead to improved cardiovascular conditioning and flexibility in sedentary female university students.