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Background: Excessive heat stress led to more than 400 deaths in the United States from 2011 to 2021. Common methods for heat injury prevention revolve around measurements of the environment and fail to account for the unique individual response to stressors.Methods: An observational approach was utilized with nine helicopter-based emergency medical services personnel during emergency flights to compare core temperature readings obtained from an ingestible temperature monitoring pill and the estimated core temperature reading of the Slate Safety Band V2 wearable device. Comparison of data was conducted within Microsoft Excel programming to determine the mean square error (MSE), root mean square error (RMSE), mean absolute error (MAE), mean biased error (MBE), and Bland–Altman plot development.Findings: A significant bias (t= 17.58, p< .001) toward the Slate Safety device reading higher with an average difference of −0.48°C (−0.86°F) was found, meaning the average temperature reading is 0.48°C (−0.86°F) higher with the Slate Safety device. A significant correlation of .26 (p< .001) was noted between the ingestible pill and the wearable device with a 95% confidence interval of 0.23 to 0.29. Aggregate core temperature data demonstrated an MSE of 0.43, an RMSE of 0.65, an MAE of 0.54, and an MBE of −0.48.Conclusions/Application to Practice: The ability to monitor the physiological parameters of a worker remotely adds safety tools relative to the risks of heat stress. The slightly higher reading associated with the Slate Safety wearable device provides an added safety margin to protect our workers.

ABSTRACTIn the context of workplace safety, activated carbon in the fiber form (i.e., activated carbon fiber, ACF) represents an alternative adsorbent to granular activated carbon (GAC) for use in organic vapor respiratory protection devices. ACFs are high surface area carbonaceous materials that are often available in a self-supporting non-woven form. The physical form of ACF suggests the potential for a filtration medium that is capable of supporting both organic vapor adsorption and particulate filtration. To study the application of these materials in respiratory protection devices, ACFs (ACFF 1200 m2/g, ACFF 1800 m2/g, and ACFF 2000 m2/g) were challenged with representative organic vapors (toluene, hexane, and methyl ethyl ketone (MEK)) at an occupationally relevant concentration (200 ppm). Breakthrough curves were generated for at least three different bed weights of adsorbent. Pressure drop (i.e., the resistance across the filtration media) was also measured to determine maximum ACF bed depths for use in respiratory protection devices. Breakthrough experiments indicate that ACFF 2000 has the highest adsorption capacity for toluene (381 mg/g), followed by ACFF 1800 and ACFF 1200 (344 mg/g and 239 mg/g, respectively). A similar trend was observed for hexane: 221 mg/g, 196 mg/g, and 146 mg/g for ACFF 2000, ACFF 1800, and ACFF 1200, respectively. ACFF 1200 showed the highest adsorption capacity for the polar adsorbate MEK (168 mg/g), followed by ACFF 1800 and ACFF 2000 (166 mg/g and 147 mg/g, respectively). Based on the constraints of pressure drop, it seems unlikely the exclusive use of ACF in a filtering facepiece respirator can provide an adsorbent mass sufficient for full shift protection against organic vapor contaminants at or above the legally enforceable permissible exposure level (PEL). Nevertheless, the incorporation of ACF into a facepiece respirator appears promising for “nuisance odor” applications; i.e., the further reduction of organic vapor concentrations when workplace exposures are already below PEL concentrations.Implications:This research brings innovation to the field of occupational health and air pollution control technology by investigating the adsorption performance of activated carbon fiber (ACF) media in the context of worker respiratory protection. ACF properties such as high specific surface area (m2/g), high permeability to airflow, and rapid adsorption kinetics make it ideal for use in thin, N95-style respirators for organic vapors. Respiratory protection is an exciting and relevant application for ACF media. A lightweight adsorbent such as ACF, if incorporated into an N95-style respirator, could potentially provide nuisance-level VOC protection in a physical form that is accessible to workers and consistent with OSHA’s voluntary use provisions for facepiece respirators. The research presented in this manuscript represents one of several steps planned in the characterization of ACF media for this particular application.

In the United States, there are more than 120,000 nail salons in which workers could be potentially exposed to a number of volatile organic compounds (VOCs) used in various procedures. Measuring workers exposure in the field is time-consuming and could be very expensive. The purpose of this study was to estimate the VOC levels in the proximity of workers in nail salons through simulating the application process of some popular nail polishes in a laboratory chamber. The worst-case scenario was defined as a worker’s exposure during nail polish application to one set of fingernails every 15 minutes for an 8-hour shift (total nail sets = 32). Nail polish was applied on paper plates in a flow-controlled test chamber. Air was sampled during the application of five different nail polishes for 8 hours using passive air samplers and the experiment was triplicated. Passive samplers were used for VOCs and formaldehyde. In this worst-case scenario setting, a total of 17 VOCs were detected, with eight that were found in all the samples. The mean concentration of butyl acetate (161-330 ppm, parts per million) and ethyl acetate (440 ppm) exceeded the threshold limit value (TLV) of 150 ppm and 400 ppm, respectively. Formaldehyde was analyzed separately and the mean concentrations exceeded the TLV of 0.10 ppm in all types of nail polish, ranging from 0.12 ppm to 0.22 ppm. Occupational safety and health professionals could use these data to increase awareness of workers’ potential exposure to high levels of VOCs in nail salons and recommend practical measures to reduce potential exposures.

Background:The food truck industry has rapidly expanded in the United States and kitchen environments can contain harmful contaminants from cooking emissions. The objective of this study was to examine the levels of aldehydes, polycyclic aromatic hydrocarbons (PAHs), and Particulate Matter (PM)2.5generated from cooking process in food trucks. Methods: Area sampling was performed twice at two participating food trucks during work shifts. Nine aldehydes and eighteeen PAHs were analyzed according to the relevant standard methods while PM2.5was measured with a real time monitor. Ventilation performance of the food truck exhaust hoods was also investigated using a thermal anemometer. Findings: Formaldehyde was the only aldehyde detected in all samples with a concentration range of 7.16 to 53.68 µg/m3. No PAHs were detected above the limit of quantification. Average PM2.5concentrations ranged from 0.65 to 7.03 mg/m3. Food Trucks 1 and 2 have an average exhaust flow rate of 211 and 215 L/s per linear meter of hood, respectively. Conclusions/Application to practice: Overall, Food Truck 2 had consistently higher levels of aldehydes and PM2.5with comparable ventilation performance as Food Truck 1. The higher exposure levels of Food Truck 2 could possibly be attributed to a larger volume of food orders and the heavy duty cooking equipment with an exhaust flow rate below the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) recommendations. Although more investigations need to be performed, the findings could be used to raise awareness of food truck workers and health practitioners to reduce potential exposure risks.

The standard method to evaluate human exposure to volatile organic compounds (VOCs) is in general performed by sampling the air on sorbents followed by liquid extraction and detection using laboratory gas chromatograph (GC). The conventional method is time and labor intensive and employs a toxic solvent which adds a risk factor as well as waste. Hence, there have been increasing demands for portable GC instruments which allow near real-time, in-situ analysis. In this study, the potential use of a prototype, dual column portable GC (protoGC) with flame ionization detector (FID) was examined by comparing its performance with a conventional GC laboratory method. Four target concentration levels (1x, 2x, 4x, and 8x; x = 1.12 ± 0.01 ppm) of toluene, ethylbenzene, and o-, m-, and p-xylene were generated in an exposure chamber (24 ± 1 °C and 50 ± 5% RH). The challenge atmosphere was directly sampled and analyzed with protoGC while for the conventional method it was sampled on a sorbent tube and analyzed with a laboratory GC/FID. The results of protoGC correlated well with the conventional method (r = 0.991–0.999), indicating that protoGC has comparable performance with the conventional method within the test conditions. Although two-way ANOVA showed significant differences in mean concentrations between the methods, the differences were small. protoGC would be useful to monitor VOCs in air with high temporal resolution or to quickly determine the safety of the environment of interest due to the substantial time savings in sampling and analysis. Further examinations at various environmental conditions and other analytes will be necessary to thoroughly evaluate its performance.