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Background Isolation gowns are one of the crucial pieces of personal protective equipment (PPE) to prevent the migration of microorganisms and body fluids from patients to health care personnel and vice versa. Underperforming isolation gowns in terms of fluid resistance, could potentially put lives in danger. Wearing multiple layers of isolation gowns could theoretically increase the fluid penetration resistance. This study investigates if 2-layer lower barrier level isolation gowns meet the barrier effectiveness requirements of a single higher barrier level isolation gown. Methods Three commonly used ANSI/AAMI Level 2 isolation gown models were selected and tested in single layer and double layer configurations in accordance with ANSI/AAMI PB70 requirements. Results Total of 240 experiments were conducted to analyze the effects of gown model, fabric region, and the number of gown layers on AATCC 127 and AATCC 42 test results. In regard to AATCC 42, there was a significant difference among the different gown models, and the number of gown layers. Similar to AATCC 42 results, there was a significant difference among the different gown models, and the number of gown layers for AATCC 127; additionally, the gown regions was also significantly different. Conclusion Test results demonstrated that the double layer isolation gown configurations do not always provide equal fluid penetration resistance as required for a single Level 3 isolation gown using the standard test methods specified in ANSI/AAMI PB70.

Objective:The coronavirus disease 2019 (COVID-19) pandemic has resulted in shortages of personal protective equipment (PPE), underscoring the urgent need for simple, efficient, and inexpensive methods to decontaminate masks and respirators exposed to severe acute respiratory coronavirus virus 2 (SARS-CoV-2). We hypothesized that methylene blue (MB) photochemical treatment, which has various clinical applications, could decontaminate PPE contaminated with coronavirus.Design:The 2 arms of the study included (1) PPE inoculation with coronaviruses followed by MB with light (MBL) decontamination treatment and (2) PPE treatment with MBL for 5 cycles of decontamination to determine maintenance of PPE performance.Methods:MBL treatment was used to inactivate coronaviruses on 3 N95 filtering facepiece respirator (FFR) and 2 medical mask models. We inoculated FFR and medical mask materials with 3 coronaviruses, including SARS-CoV-2, and we treated them with 10 µM MB and exposed them to 50,000 lux of white light or 12,500 lux of red light for 30 minutes. In parallel, integrity was assessed after 5 cycles of decontamination using multiple US and international test methods, and the process was compared with the FDA-authorized vaporized hydrogen peroxide plus ozone (VHP+O3) decontamination method.Results:Overall, MBL robustly and consistently inactivated all 3 coronaviruses with 99.8% to >99.9% virus inactivation across all FFRs and medical masks tested. FFR and medical mask integrity was maintained after 5 cycles of MBL treatment, whereas 1 FFR model failed after 5 cycles of VHP+O3.Conclusions:MBL treatment decontaminated respirators and masks by inactivating 3 tested coronaviruses without compromising integrity through 5 cycles of decontamination. MBL decontamination is effective, is low cost, and does not require specialized equipment, making it applicable in low- to high-resource settings.

The barrier properties of personal protective equipment are vital to healthcare personnel to protect themselves from possible infectious body fluids. Intraoperative exposure of healthcare personnel to body fluids can be substantial in both inpatient and outpatient settings. The glove–gown interface is known as one of the weakest points of the whole personal protective equipment system. However, there is a lack of scientific research designed to investigate the problem. This paper reports the results of experiments using a new testing methodology developed to quantify fluid leakage through the glove–gown interface while simulating surgical settings in terms of operating room personnel activities, exposure types, exposure durations, and physical stresses applied on the interface. This study represents one of the first efforts investigating the amount of fluid leakage through the glove–gown interface for a number of surgical gown and glove models while considering glove material differences and single vs. double gloving. The test results showed that there is a significant difference in fluid leakage amounts between three gown models and four glove models studied. The results also demonstrated that double gloving significantly reduced the fluid leakage compared to single glove use. The mean fluid leakage was lower in the double synthetic glove configurations (M = 2.76g) compared with all other configurations (3GLV, M = 8.3g; 4GLV, M = 9.49g; 5GLV, M = 3.08g; 6GLV, M = 20.03g; double latex, M = 5.22g). Findings highlighted a significant interaction between glove and gown designs, which suggests that gown and gloves should be designed together as a system to minimize or eliminate the fluid leakage.

Background Isolation gowns are recommended to protect healthcare personnel, patients, and visitors from transfer of microorganisms and body fluids in patient isolation situations. Standards provide limited information about barrier performance of isolation gowns for possible exposure scenarios. One of the most vulnerable areas of the personal protective equipment ensemble is considered the glove-gown interface. However, current isolation gown classification standards do not consider the interface regions of the personal protective equipment system while assessing the level of protection. The purpose of this study was to quantitatively evaluate the fluid leakage through the glove-gown interface by simulating exposures and healthcare personnel arm movements in patient care for isolation settings. Methods We tested fluid leakage of two examination gloves with different cuff lengths and seven isolation gown models designed with varying levels of barrier resistance and multiple cuff types. Results Our results demonstrated that leakage through the glove-gown interface depends on multiple factors, including glove cuff length and gown cuff design. Gowns with the thumb loop design provided better protection than the elastic cuff design, and the elastic cuff design provided better protection compared to the knit cuff design for a given AAMI PB70 level. More importantly, a substantial penetration through gown fabrics was observed. Conclusions This research identifies a need to develop a standardized method to evaluate leakage at the glove-gown interface to improve worker protection.

BackgroundThe coronavirus disease 2019 (COVID-19) pandemic has resulted in severe shortages of personal protective equipment (PPE) necessary to protect front-line healthcare personnel. These shortages underscore the urgent need for simple, efficient, and inexpensive methods to decontaminate SARS-CoV-2-exposed PPE enabling safe reuse of masks and respirators. Efficient decontamination must be available not only in low-resourced settings, but also in well-resourced settings affected by PPE shortages. Methylene blue (MB) photochemical treatment, hitherto with many clinical applications including those used to inactivate virus in plasma, presents a novel approach for widely applicable PPE decontamination. Dry heat (DH) treatment is another potential low-cost decontamination method.MethodsMB and light (MBL) and DH treatments were used to inactivate coronavirus on respirator and mask material. We tested three N95 filtering facepiece respirators (FFRs), two medical masks (MMs), and one cloth community mask (CM). FFR/MM/CM materials were inoculated with SARS-CoV-2 (a Betacoronavirus), murine hepatitis virus (MHV) (a Betacoronavirus), or porcine respiratory coronavirus (PRCV) (an Alphacoronavirus), and treated with 10 µM MB followed by 50,000 lux of broad-spectrum light or 12,500 lux of red light for 30 minutes, or with 75°C DH for 60 minutes. In parallel, we tested respirator and mask integrity using several standard methods and compared to the FDA-authorized vaporized hydrogen peroxide plus ozone (VHP+O3) decontamination method. Intact FFRs/MMs/CM were subjected to five cycles of decontamination (5CD) to assess integrity using International Standardization Organization (ISO), American Society for Testing and Materials (ASTM) International, National Institute for Occupational Safety and Health (NIOSH), and Occupational Safety and Health Administration (OSHA) test methods.FindingsOverall, MBL robustly and consistently inactivated all three coronaviruses with at least a 4-log reduction. DH yielded similar results, with the exception of MHV, which was only reduced by 2-log after treatment. FFR/MM integrity was maintained for 5 cycles of MBL or DH treatment, whereas one FFR failed after 5 cycles of VHP+O3. Baseline performance for the CM was variable, but reduction of integrity was minimal.InterpretationMethylene blue with light and DH treatment decontaminated masks and respirators by inactivating three tested coronaviruses without compromising integrity through 5CD. MBL decontamination of masks is effective, low-cost and does not require specialized equipment, making it applicable in all-resource settings. These attractive features support the utilization and continued development of this novel PPE decontamination method.

During epidemics and pandemics healthcare personnel (HCP) are on the front line of disease containment and mitigation. Personal protective equipment (PPE), such as NIOSH-approved N95 filtering facepiece respirators (FFRs), serve an important role in minimizing HCP risks and are in high demand during public health emergencies. Because PPE demand can exceed supply, various public health strategies have been developed to reduce the rate of PPE consumption as supply dwindles. Extended use and limited reuse of N95 FFRs are strategies advocated by many governmental agencies used to increase the number of times a device can be used. Increased use of respirators designed for reuse—such as powered air-purifying respirators (PAPRs) and elastomeric half-mask and full facepiece air-purifying respirators— is another option designed to reduce the continuous need for new devices as the daily need for respirator use increases. Together, these strategies are designed to reduce the number of PPE units that must be discarded daily and, therefore, extend the longevity of available supply. The purpose of this paper is to theoretically estimate the impact of extended use and limited reuse strategies for N95 FFRs and the increased use of reusable respirator options on PPE consumed. The results suggest that a considerable reduction in PPE consumption would result from extended use and limited reuse of N95 FFRs and the increased use of respirators designed for reuse; however, the practical benefits must be balanced with the risks and economic costs. In addition, extended use and reuse strategies must be accompanied by proper procedures to reduce risk. The study is designed to support epidemic and pandemic PPE supply and demand planning efforts.

The COVID-19 pandemic is currently causing a severe disruption and shortage in the global supply chain of necessary personal protective equipment (e.g., N95 respirators). The U.S. CDC has recommended use of household cloth by the general public to make cloth face coverings as a method of source control. We evaluated the filtration properties of natural and synthetic materials using a modified procedure for N95 respirator approval. Common fabrics of cotton, polyester, nylon, and silk had filtration efficiency of 5–25%, polypropylene spunbond had filtration efficiency 6–10%, and paper-based products had filtration efficiency of 10–20%. An advantage of polypropylene spunbond is that it can be simply triboelectrically charged to enhance the filtration efficiency (from 6 to >10%) without any increase in pressure (stable overnight and in humid environments). Using the filtration quality factor, fabric microstructure, and charging ability, we are able to provide an assessment of suggested fabric materials for homemade facial coverings.

Background Exposure to patients' blood/body fluids could be life-affecting, when providing care to patients with infectious diseases. Although the glove-gown interface is considered one of the weakest points of the protective ensemble system, there is a lack of research, and existing standards do not provide much guidance on strategies to minimize gaps between the gowns and gloves. Currently, there is no known standard test method to evaluate fluid leakage or assess performance improvements with new gowns/gloves. Study Design A novel test method with a robotic arm, which has the capability to simulate health care personnel's arm movements during fluid exposure, was developed to determine the leakage at the glove-gown interface. This article explains the test method and investigates the effect of movement, exposure type, exposure duration, procedure duration, and existence of pressure on the amount of leaked fluid at the glove-gown interface. Results Test results suggest that, with the exception of procedure duration, all parameters significantly affected the amount of fluid leaked at the glove-gown interface. Leakage was higher for soaking when compared to spraying, increased as the exposure duration increased, and was greater with the application of pressure. Conclusions The novel method developed in this study could be used by manufacturers of personal protective equipment to evaluate their products. Standard development organizations could adapt this test method in their specifications, testing standards, and guidelines.

BackgroundIn epidemics of highly infectious diseases, such as Ebola, severe acute respiratory syndrome (SARS), or coronavirus (COVID‐19), healthcare workers (HCW) are at much greater risk of infection than the general population, due to their contact with patients' contaminated body fluids. Personal protective equipment (PPE) can reduce the risk by covering exposed body parts. It is unclear which type of PPE protects best, what is the best way to put PPE on (i.e. donning) or to remove PPE (i.e. doffing), and how to train HCWs to use PPE as instructed.ObjectivesTo evaluate which type of full‐body PPE and which method of donning or doffing PPE have the least risk of contamination or infection for HCW, and which training methods increase compliance with PPE protocols.Search methodsWe searched CENTRAL, MEDLINE, Embase and CINAHL to 20 March 2020.Selection criteriaWe included all controlled studies that evaluated the effect of full‐body PPE used by HCW exposed to highly infectious diseases, on the risk of infection, contamination, or noncompliance with protocols. We also included studies that compared the effect of various ways of donning or doffing PPE, and the effects of training on the same outcomes.Data collection and analysisTwo review authors independently selected studies, extracted data and assessed the risk of bias in included trials. We conducted random‐effects meta‐analyses were appropriate.Main resultsEarlier versions of this review were published in 2016 and 2019. In this update, we included 24 studies with 2278 participants, of which 14 were randomised controlled trials (RCT), one was a quasi‐RCT and nine had a non‐randomised design.Eight studies compared types of PPE. Six studies evaluated adapted PPE. Eight studies compared donning and doffing processes and three studies evaluated types of training. Eighteen studies used simulated exposure with fluorescent markers or harmless microbes. In simulation studies, median contamination rates were 25% for the intervention and 67% for the control groups.Evidence for all outcomes is of very low certainty unless otherwise stated because it is based on one or two studies, the indirectness of the evidence in simulation studies and because of risk of bias.Types of PPEThe use of a powered, air‐purifying respirator with coverall may protect against the risk of contamination better than a N95 mask and gown (risk ratio (RR) 0.27, 95% confidence interval (CI) 0.17 to 0.43) but was more difficult to don (non‐compliance: RR 7.5, 95% CI 1.81 to 31.1). In one RCT (59 participants) coveralls were more difficult to doff than isolation gowns (very low‐certainty evidence). Gowns may protect better against contamination than aprons (small patches: mean difference (MD) −10.28, 95% CI −14.77 to −5.79). PPE made of more breathable material may lead to a similar number of spots on the trunk (MD 1.60, 95% CI −0.15 to 3.35) compared to more water‐repellent material but may have greater user satisfaction (MD −0.46, 95% CI −0.84 to −0.08, scale of 1 to 5). According to three studies that tested more recently introduced full‐body PPE ensembles, there may be no difference in contamination.Modified PPE versus standard PPEThe following modifications to PPE design may lead to less contamination compared to standard PPE: sealed gown and glove combination (RR 0.27, 95% CI 0.09 to 0.78), a better fitting gown around the neck, wrists and hands (RR 0.08, 95% CI 0.01 to 0.55), a better cover of the gown‐wrist interface (RR 0.45, 95% CI 0.26 to 0.78, low‐certainty evidence), added tabs to grab to facilitate doffing of masks (RR 0.33, 95% CI 0.14 to 0.80) or gloves (RR 0.22, 95% CI 0.15 to 0.31).Donning and doffingUsing Centers for Disease Control and Prevention (CDC) recommendations for doffing may lead to less contamination compared to no guidance (small patches: MD −5.44, 95% CI −7.43 to −3.45). One‐step removal of gloves and gown may lead to less bacterial contamination (RR 0.20, 95% CI 0.05 to 0.77) but not to less fluorescent contamination (RR 0.98, 95% CI 0.75 to 1.28) than separate removal. Double‐gloving may lead to less viral or bacterial contamination compared to single gloving (RR 0.34, 95% CI 0.17 to 0.66) but not to less fluorescent contamination (RR 0.98, 95% CI 0.75 to 1.28). Additional spoken instruction may lead to fewer errors in doffing (MD −0.9, 95% CI −1.4 to −0.4) and to fewer contamination spots (MD −5, 95% CI −8.08 to −1.92). Extra sanitation of gloves before doffing with quaternary ammonium or bleach may decrease contamination, but not alcohol‐based hand rub.TrainingThe use of additional computer simulation may lead to fewer errors in doffing (MD −1.2, 95% CI −1.6 to −0.7). A video lecture on donning PPE may lead to better skills scores (MD 30.70, 95% CI 20.14 to 41.26) than a traditional lecture. Face‐to‐face instruction may reduce noncompliance with doffing guidance more (odds ratio 0.45, 95% CI 0.21 to 0.98) than providing folders or videos only.Authors' conclusionsWe found low‐ to very low‐certainty evidence that covering more parts of the body leads to better protection but usually comes at the cost of more difficult donning or doffing and less user comfort. More breathable types of PPE may lead to similar contamination but may have greater user satisfaction. Modifications to PPE design, such as tabs to grab, may decrease the risk of contamination. For donning and doffing procedures, following CDC doffing guidance, a one‐step glove and gown removal, double‐gloving, spoken instructions during doffing, and using glove disinfection may reduce contamination and increase compliance. Face‐to‐face training in PPE use may reduce errors more than folder‐based training.We still need RCTs of training with long‐term follow‐up. We need simulation studies with more participants to find out which combinations of PPE and which doffing procedure protects best. Consensus on simulation of exposure and assessment of outcome is urgently needed. We also need more real‐life evidence. Therefore, the use of PPE of HCW exposed to highly infectious diseases should be registered and the HCW should be prospectively followed for their risk of infection.

Although they play an important role in infection prevention and control, textile materials and personal protective equipment (PPE) used in health care settings are known to be one of the sources of cross-infection. Gowns are recommended to prevent transmission of infectious diseases in certain settings; however, laboratory and field studies have produced mixed results of their efficacy. PPE used in health care is regulated as either class I (low risk) or class II (intermediate risk) devices in the United States. Many organizations have published guidelines for the use of PPE, including isolation gowns, in health care settings. In addition, the Association for the Advancement of Medical Instrumentation published a guidance document on the selection of gowns and a classification standard on liquid barrier performance for both surgical and isolation gowns. However, there is currently no existing standard specific to isolation gowns that considers not only the barrier resistance but also a wide array of end user desired attributes. As a result, infection preventionists and purchasing agents face several difficulties in the selection process, and end users have limited or no information on the levels of protection provided by isolation gowns. Lack of knowledge about the performance of protective clothing used in health care became more apparent during the 2014 Ebola epidemic. This article reviews laboratory studies, regulations, guidelines and standards pertaining to isolation gowns, characterization problems, and other potential barriers of isolation gown selection and use.