Journal of occupational and environmental hygiene
-
J Occup Environ Hyg · Jan 2016
A method for evaluating aerosol leakage through the interface between protective suits and full-face respirators.
Military personnel and first responders use a range of personal equipment including protective suits, gloves, boots, and respirators to prevent exposure of their skin and airways to hazardous chemical, biological, radiological, and/or nuclear substances. Although each individual item of personal protective equipment is well tested against existing standards, it is also necessary to consider the performance of the interfaces between items in terms of prevention from exposure, and the protection system as a whole. This article presents an aerosol challenge method for assessing the performance of the interface between a respirator and the hood of a protective suit. ⋯ Different leakage patterns were observed for the three respirators and were linked to some specific design features, namely the respirator's sealing area at the chin and its width at cheek level. Induced leak experiments showed that to detect substantial particle leakage, channels at the hood-respirator interface must be quite large. The method outlined herein provides a straightforward way of evaluating hood-respirator interfaces and could be useful in the further development of personal protective equipment.
-
J Occup Environ Hyg · Jan 2016
Predictors of adherence to safe handling practices for antineoplastic drugs: A survey of hospital nurses.
Despite growing awareness of the hazards of exposure to antineoplastic drugs (ADs), surveys continue to find incomplete adherence to recommended safe handling guidelines. A 2011 survey of healthcare workers presents an opportunity to examine factors associated with adherence among 1094 hospital nurses who administered ADs. Data for these hypothesis-generating analyses were taken from an anonymous, web-based survey of healthcare workers. ⋯ AD administration frequency was also associated with performing more activities with gloves previously worn to administer ADs, and nurse perception of having adequate time for taking safety precautions with fewer such activities. The results suggest that training and familiarity with guidelines for safe handling of ADs, adequate time to adhere to guidelines, and availability of PPE and certain engineering controls are key to ensuring adherence to safe handling practices. Further assessment of training components and engineering controls would be useful for tailoring interventions targeting these areas.
-
J Occup Environ Hyg · Jan 2016
Performance of an improperly sized and stretched-out loose-fitting powered air-purifying respirator: Manikin-based study.
The objective of this study was to investigate the protection level offered by a Powered Air-Purifying Respirator (PAPR) equipped with an improperly sized or stretched-out loose-fitting facepiece using constant and cyclic flow conditions. Improperly sized PAPR facepieces of two models as well as a stretched-out facepiece were tested. These facepieces were examined in two versions: with and without exhaust holes. ⋯ The time-weighted average values of mFF calculated from the measurements conducted under the constant flow regime were capable of predicting the protection under cyclic flow regime. The findings suggest that program administrators need to equip employees with properly sized facepieces and remove stretched-out ones from workplace. Manufacturers should emphasize the importance of proper sizing with their user instructions.
-
J Occup Environ Hyg · Jan 2016
Investigation of the flow-field in the upper respiratory system when wearing N95 filtering facepiece respirator.
This article presents a reverse modeling of the headform when wearing a filtering facepiece respirator (FFR) and a computational fluid dynamics (CFD) simulation based on the modeling. The whole model containing the upper respiratory airway, headform, and FFR was directly recorded by computed tomography (CT) scanning, and a medical contrast medium was used to make the FFR "visible." The FFR was normally worn by the subject during CT scanning so that the actual deformation of both the FFR and the face muscles during contact can be objectively conserved. The reverse modeling approach was introduced to rebuild the geometric model and convert it into a CFD solvable model. ⋯ The air temperature in the FFR cavity increases rapidly at first and then stays close to the exhaled temperature. Compared to not wearing an FFR, wearers have to increase approximately 90 Pa more pressure to keep the same breathing flow rate of 30.54 L/min after wearing an FFR. The nasal vestibule bears more wall shear stress than any other area in the airway.
-
J Occup Environ Hyg · Jan 2016
Respiratory protection for firefighters--Evaluation of CBRN canisters for use during overhaul II: In mask analyte sampling with integrated dynamic breathing machine.
According to the National Fire Protection Association there were 487,500 structural fires in the U. S. in 2013. After visible flames are extinguished firefighters begin the overhaul stage where remaining hot spots are identified and further extinguished. ⋯ Acetaldehyde and formaldehyde were found to be the only two chemicals detected post filter but were effectively filtered to below ACGIH TLVs. Counter to our prior published work using continuous flow filter evaluation, this study indicates that, regardless of brand, CBRN filters were effective at reducing concentrations of post-fire ambient chemicals to below occupational exposure limits. However, caution should be applied when using CBRN filters as the ambient formaldehyde level in the current study was 8.9 times lower than during the previous work.