Impermeable Suit Research Articles

Painting the Gown Red: Using a Colored Paint Quality Improvement Process to Evaluate Healthcare Worker Personal Protective Equipment for Highly Pathogenic Infections

BackgroundPersonal protective equipment (PPE) and strict infection control techniques are the primary methods by which healthcare workers (HCW) can avoid exposure during the treatment of patients with highly pathogenic infections such as Ebola Virus Disease (EVD) or the Middle East Respiratory Syndrome coronavirus (MERS-CoV). There is currently no consensus for the types of PPE that are recommended to be worn by HCWs, nor is there a universal process for the donning and doffing of PPE.MethodsHCWs from Bellevue Hospital participate in quarterly PPE trainings as part of the Special Pathogens Program (SPP), which consist of didactic sessions as well as an evaluation of donning and doffing techniques. A total of 50 HCWs completed the training curriculum in 2017. During the doffing process, PPE trainers applied corn start powder paint (Chameleon Colors; American Fork, UT) to the participants’ gloved hands between multiple steps of PPE removal. At the end of the process, the areas where paint was found on was documented including the outer surgical gown, the powered air purifying respirator (PAPR) helmet and shroud, the inner impermeable suit, the knee-high boots and boot covers, and the extended-cuff gloves.ResultsThe areas of PPE that were most marked with paint were the lower shoulders and upper arms of the surgical gowns, the top sides of the PAPR shroud, the front upper chest area, and the center back of the inner impermeable suits. In a majority of cases no powder paint was noted on the knee-high boots. In a minority of cases, paint was observed on the inside upper chest area of the surgical gown. These paint markings were used to discuss potential breaches in PPE doffing technique in real-time, as well as identify areas to target in future PPE trainings.ConclusionThe powdered paint quality improvement process for donning and doffing PPE is a method to evaluate the complex PPE dressing procedure. It is particularly useful given the fact that it is incumbent on each hospital or healthcare system to develop its own processes and procedures for PPE, as well as maintain readiness through periodic trainings. Powdered paint can identify vulnerabilities in their process as well as areas that require further education.Disclosures All authors: No reported disclosures.

Variability in Human Responses when working in Chemical protective Impermeable Suits

Variability in Human Responses when working in Chemical protective Impermeable Suits

Variability in Heat Strain in Fully Encapsulated Impermeable Suits in Different Climates and at Different Work Loads.

A major concern for responders to hazardous materials (HazMat) incidents is the heat strain that is caused by fully encapsulated impermeable (NFPA 1991) suits. In a research project, funded by the US Department of Defense, the thermal strain experienced when wearing these suits was studied. Forty human subjects between the ages of 25 and 50 participated in a protocol approved by the local ethical committee. Six different fully encapsulated impermeable HazMat suits were evaluated in three climates: moderate (24°C, 50% RH, 20°C WBGT), warm-wet (32°C, 60% RH, 30°C WBGT), and hot-dry (45°C, 20% RH, 37°C WBGT, 200 W m-2 radiant load) and at three walking speeds: 2.5, 4, and 5.5 km h-1. The medium speed, 4 km h-1, was tested in all three climates and the other two walking speeds were only tested in the moderate climate. Prior to the test a submaximal exercise test in normal clothing was performed to determine a relationship between heart rate and oxygen consumption (pretest). In total, 163 exposures were measured. Tolerance time ranged from as low as 20 min in the hot-dry condition to 60 min (the maximum) in the moderate climate, especially common at the lowest walking speed. Between the six difference suits limited differences were found, a two-layered aluminized suit exhibited significant shorter tolerance times in the moderate climate, but no other major significant differences were found for the other climates or workloads. An important characteristic of the overall dataset is the large variability between the subjects. Although the average responses seem suitable to be predicted, the variability in the warmer strain conditions ranged from 20 min up to 60 min. The work load in these encapsulated impermeable suits was also significantly higher than working in normal clothing and higher than predicted by the Pandolf equation. Heart rate showed a very strong correlation to body core temperature and was in many cases the limiting factor. Setting the heart rate maximum at 80% of predicted individual maximum (age based) would have prevented 95% of the cases with excessive heat strain. Monitoring of heart rate under operational conditions would further allow individually optimize working times and help in preventing exertional heat stroke.

Combined thermal manikin and thermal model predictions of working times in fully encapsulated impermeable suits

This project aimed to develop guidelines for safe working times in fully encapsulated impermeable suits and incorporate these data into an existing Chemical Companion Decision Support System (CCDSS) that is used by First responders in the US and abroad. The CCDSS provides guidelines on many operational aspects of response to a hazardous materials (HazMat). This study addresses the use of a thermos-physiological model, combined with a sweating thermal manikin, to simulate the data and compared that to the experimental data.

A Review on NBC Body Protective Clothing

Body protective clothing and suits against NBC agents are playing vital role in the NBC defence during war and training scenarios. Hence, reviewing about the past, present and expected future development in this NBC protective clothing area is an important task. This review brings out a sequence related to the NBC protective clothing, their type, various materials available for the development of NBC clothing, their evaluation procedures, washing methodologies, decontamination methods. Moreover, the futuristic trends in NBC protective clothing such as detection and decontamination integrated NBC protective clothing based on electrospun nanofiber technology and molecularly imprinted polymer technology are also reviewed and discussed. 1. GENERAL INTRODUCTION The protective clothing used in the World War I against chemical warfare agents (CWA) consisted of rubber clothing, which, together with gloves and boots, to cover the entire body apart from that protected by the mask. Clothing of this kind is usually characterized as impermeable. This means that CW agents cannot pass through the material and also the fact that perspiration released from the skin is also prevented from passing out. Consequently, to wear clothing of this kind for longer periods is extremely uncomfortable and in hot climates the period during which protective clothing of this kind can be worn will be very short. In order to reduce the heat load developed due to wearing of impermeable protective clothing, permeable clothing was designed and developed, where a layer of finely distributed active carbon, either bound in polyurethane foam or as particles of carbon, is bound between two layers of textile. A layer of this kind consisting of active carbon which permits water vapour released from the body to pass through. The active carbon absorbs CWA and thereby prevents them from passing through to the skin. This layer of carbon is never used alone but is combined with different textiles. A present CWA protective suit is an example of clothing made of permeable material. The largest difference is that inside the impregnated outer material there is a layer of active carbon on a suitable carrier. The CWA protective suit can be used instead of a battle dress or as an overall placed over the uniform. An alternative is to use inner clothing with a layer of carbon which is worn underneath the normal uniform. Impermeable suits can be used in severely contamina- ted environments, e.g., during decontamination. The heat load can be reduced by ventilating the clothing with fans. However, this solution is too vulnerable to be used.

Thermal responses and physiological strain in men wearing impermeable and semipermeable protective clothing in the cold

The purpose of the present study was to examine the effects of long term cold exposure on thermal responses and physical performance in men while wearing nuclear, biological and chemical (NBC) protective clothing. Six healthy men performed 60min work/60min rest cycles during 8 hours at an ambient temperature of-10°C. Work was performed by stepping on a 20cm high bench 15 times' min-1. Subjects were tested while wearing two different types of NBC clothing: impermeable rubber suit (IP) or semipermeable charcoal impregnated suit (SP) with cold weather underwear layers, as well as rubber gloves, boots and a. full-face mask. During the tests oxygen consumption (VO2), rectal (Tre) and skin temperatures and sweat production were measured. Rectal and skin temperatures and body heat content followed the work/rest cycles in both types of NBC clothing. Tre averaged 37.1 ± 0.04 and 37.3 ± 0.1°C for IP and SP (NS), respectively. On average, mean skin temperature (Tsk) was 28.6 ± 0.2 and 29.7 ± 0.2°C for IP and SP (p < 0.01), respectively. Finger skin temperature decreased rapidly to below 10°C in both ensembles during the rest periods. During work the finger rewarming rate was 0.49 ± 0.06 and 0.70 ± 0.02°C min-1 for IP and SP (p < 0.01), respectively. Decrease in body heat storage (S) during cold exposure was smaller in SP than in IP and S was restored to the level of- 0.6 ± 0.3 and - 3.0 ± 0.6kJ kg-1 in SP and IP (p < 0 01), respectively, during the work. Work load, according to VO2 measurements, was 1.5 ± 0.1 and 1.3 ± 0.1 1 min-1 for IP and SP (p < 0.05), respectively. Furthermore, during rest VO2 was 30% (p < 0.001) higher in IP than in SP. In conclusion, both types of NBC protective clothing could be used for long periods in cold conditions at a moderate work load without marked whole body heat debt or heat load. However, peripheral parts of the body experienced a rapid and severe cooling during the rest periods. The semipermeable suit enabled higher body heat storage and faster rewarming of extremities during work than the impermeable suit.

Validation of a Personal Heat Stress Monitor

The purpose of this study was to test the validity of the Metrosonics, Inc. hs-3800 personal heat strain monitor in predicting deep-body temperature, measured with a rectal probe (Tre). Fifteen males participated in two sessions walking and arm curling at 300 Kcal/hr for up to 2 hours each in a 26°C wet bulb globe temperature environment wearing two different types of particle barrier, vapor permeable suits common to industry: a melt-blown spunbond polypropylene laminate (PPPC) and a flash-spunbond polyethylene (PEPC), subsequently compared for test-retest reliability. Eight of these subjects performed a third test while wearing an impermeable suit made from Saranex® (coated PEPC) (SAR). Correlations between the hs-3800 and Tre for PPPC were r = 0.58 and r=0.53 for SAR. In the first test of hs-3800 in PPPC, 0 true positives (TP), 10 true negatives (TN), 2 false positives (FP), and 3 false negatives (FN) were observed, yielding a specificity of the hs-3800 in PPPC of 78%. In the subsequent tests of the hs-...

Effects of local restriction of evaporation and moderate local ventilation on thermoregulatory responses in exercising humans.

Ten healthy young men participated in two series of three trials: series 1 (C1) with, or without, local restriction of evaporation (either on the trunk or on the legs) and series 2 (C2) with, or without, local moderate nitrogen ventilation (40 l.min-1) under an impermeable garment (trunk or leg ventilation). After 60-min rest in a thermoneutral environment, the subjects exercised in a warm environment [30 degrees C, 47% relative humidity (rh) during C1 and 29% rh during C2] on a cycle ergometer for 60 min at 70 W during C1 or at 60 W during C2. During C1, local covering with plastic foil did not increase internal temperature, but increased the mean skin temperature with a higher effect in the case of leg restriction. The trunk skin temperature was affected by the leg covering while the leg skin temperature was not changed by the trunk covering. Only the local sweat rate of the trunk was increased by the two restriction conditions. During C2, internal temperature was decreased by local ventilation while mean skin temperature was reduced only by trunk ventilation. The local ventilation affected only trunk skin temperature with a greater decrease during trunk ventilation. Trunk ventilation did not influence the skin temperature of the legs while ventilation of the legs decreased trunk skin temperature. In addition, leg ventilation decreased the sweat rate of the legs. The impermeable suit worn during C2 led to a greater physiological strain compared to the plastic film worn during C1 even with local ventilation under the impermeable garment. As expected, limiting sweat evaporation led to an increase in physiological strain. Microclimate ventilation at a rate of 40 l.min-1 was not sufficient to allow total heat dissipation but allowed 60-min exercise in a warm environment to be completed without excessive heat accumulation. It would appear that ventilation of the trunk locally was the best solution because of the smaller increase in skin temperature and higher sweating capacity of the trunk.

Clothing as a dynamic system presenting problems in predicting performance

Prediction of the performance of personnel undertaking physical work in a hot environment is generally achieved by the use of factors for work rate, clothing and climate. A study is reported in which volunteer subjects worked at a fixed rate in five different climates wearing two different clothing assemblies, one semi-permeable, the other impermeable to water vapour. In addition to assessing likely work times in the various climate and clothing combinations, an analysis of the climatic predictors of performance has been undertaken. Whereas in the impermeable suit, predicted work times appeared to be based almost solely on the dry bulb temperature, those in the semi-permeable clothing were well predicted by the WBGT Index. There was no indication that this index would have a greater weighting for the dry bulb component, despite the clothing being partly restrictive to water vapour. If any adjustment is necessary it should be to slightly increase the weighting of the wet bulb.

Cardiorespiratory and thermal effects of wearing gas protective clothing.

Six healthy men aged 25 to 37 walked on a treadmill at work levels of 21 and 41% of their VO2max for 25 to 30 min wearing gas protective clothing (GPC) consisting of an impermeable suit with a self-contained breathing apparatus (total weight 25 kg) or shorts (control tests, CT) in a temperate environment (ta 24.3 degrees C +/- 1.0 degrees C, rh 30-50%). When the GPC was worn at 21 and 41% VO2max, the most prominent increases, compared with the CT, were noted in the heart rate (means +/- SE, 120 +/- 5 vs 76 +/- 3 beats min-1 and 171 +/- 5 vs 103 +/- 3 beats min-1), mean skin temperature (36.1 +/- 0.2 vs 31.3 degrees C +/- 0.1 degree C and 36.9 +/- 0.3 vs 30.9 degrees C +/- 0.4 degrees C) and sweat rate (473 +/- 51 vs 70 +/- 23 g m-2 h-1 and 766 +/- 81 vs 135 +/- 18 g m-2 h-1) indicating a high cardiovascular and thermoregulatory strain, which was not decreased by ventilating the suit with an air flow of 281 min-1 at 41% VO2max. The ventilation, oxygen consumption and production of carbon dioxide increased in relation to the extra weight of the GPC, partly dependent on the dynamic work level. It was concluded that the increase in the physiological load caused by the GPC was so high that the work-rest regimens, workers' level of physical fitness, cardiovascular health and heat tolerance should be considered whenever gas protective clothing is used.

Stresses involved in wearing PVC supplied-air suits: a review

A side effect of the growth and development of industrial technology is the ever increasing number of hostile environments encountered by man. This situation has resulted in the development of impermeable clothing as a barrier protection against the external environment. Unfortunately, although specific government standards concerning the design and engineering requirements of the impermeable suit have been stated, little or no standardized evaluation of the majority of available suits has been attempted. This review was undertaken to provide an in-depth summary of the physiological effects of a PVC protective suit while working. It was concluded that it was necessary to develop a standardized performance test to determine the protective and stressful characteristics of the individual manufacturer's designed suit. Recommendations of specific criteria for the test were obtained.

Physiological effects on word performance of vapor-barrier clothing and full-face respirator.

Work performance with impervious clothing and full-face respirator was investigated during maximal and submaximal (40-60%) bicycle ergometer efforts. Such levels may be dictated by the requirements of emergency decontamination tasks while most studies have been concerned with lower levels of activity. Five different exercise protocols were administered. Heart rate (HR), oxygen consumption (Vo2), skin (Ts) and rectal (Tr) temperatures were monitored. The impervious suits resulted in decreased work performance, aerobic metabolism, and tolerance time. Stress indices of HR and mean Ts were found to be correlated with these differences. The study is being expanded for the purpose of establishing safe physiological guidelines for work tolerances at higher energy levels in impermeable suits.