Personal Protective Equipment Decontamination Research Articles

APDI meets PPE: photochemical decontamination in healthcare using methylene blue-where are we now, where will we go?

Personal protective equipment (PPE) reuse, first recommended in the context of the SARS-CoV-2 pandemic, can mitigate shortages in crisis situations and can greatly reduce the environmental impact of typically single-use PPE. Prior to safe reuse, PPE must be sanitized and contaminating pathogens-in current circumstances viruses in particular-must be inactivated. However, many established decontamination procedures are not equitable and remain unavailable in low-resource settings. In mid-2020, an interdisciplinary consortium of researchers first studied the potential of implementing cheap and easy-to-use antimicrobial photodynamic inactivation (aPDI) using methylene blue as photosensitizer to decontaminate face masks and filtering facepiece respirators. In this perspective piece, we describe the development of this novel method, discuss recent advances, and offer insights into how equitable PPE decontamination via methylene blue-based aPDI may be integrated into circular economy policies in the healthcare sector.

Exploration of Eco-Friendly Hydrochar’s Potential in Advanced Oxidative Processes for Dicamba Degradation within a Circular Bio-Economy Framework

Dicamba, renowned for its limited sorption capacity, presents a substantial risk of contaminating surface and groundwater if the disposal of spray tank effluent is not adequately controlled. In this work, a dicamba effluent underwent treatment through a Fenton-like process employing an iron/hydrochar (Hy-Fe) composite, synthesized via hydrothermal methods using coffee husk as the precursor. The Hy-Fe displayed carbon, hydrogen, and nitrogen levels of 52.30%, 5.21%, and 1.49%, respectively. Additionally, the material exhibited a specific surface area measuring 9.00 m2 g−1. The presence of the γ-Fe2O3 phase within the composite was confirmed through X-ray diffraction analysis. The Fenton-like process employing Hy-Fe demonstrated approximately 100% degradation of dicamba within 5 h. The treated effluent underwent toxicity evaluation via biological assays using beans (Phaseolus vulgaris) as indicator plants, revealing no observable signs of intoxication. These findings were corroborated by High-Performance Liquid Chromatography, providing additional confirmation of the degradation results. Additionally, decontamination of personal protective equipment potentially contaminated with dicamba was also assessed. The Hy-Fe composite demonstrated reusability across three degradation cycles, achieving degradation percentages of 100%, 70%, and 60%, respectively. The Hy-Fe composite demonstrates substantial potential for use in a Fenton-like process. This process is characterized by its simplicity, speed, and sustainability. The notable effectiveness, evidenced by high degradation rates and minimal toxicity, underscores its suitability as a practical solution for addressing dicamba contamination.

Ozone Decontamination of Medical and Nonmedical Devices: An Assessment of Design and Implementation Considerations.

The control of infectious diseases can be improved via carefully designed decontamination equipment and systems. Research interest in ozone (a powerful antimicrobial agent) has significantly increased over the past decade. The COVID-19 pandemic has also instigated the development of new ozone-based technologies for the decontamination of personal protective equipment, surfaces, materials, and indoor environments. As this interest continues to grow, it is necessary to consider key factors affecting the applicability of lab-based findings to large-scale systems utilizing ozone. In this review, we present recent developments on the critical factors affecting the successful deployments of industrial ozone technologies. Some of these include the medium of application (air or water), material compatibility, efficient circulation and extraction, measurement and control, automation, scalability, and process economics. We also provide a comparative assessment of ozone relative to other decontamination methods/sterilization technologies and further substantiate the necessity for increased developments in gaseous and aqueous ozonation. Modeling methodologies, which can be applied for the design and implementation of ozone contacting systems, are also presented in this review. Key knowledge gaps and open research problems/opportunities are extensively covered including our recommendations for the development of novel solutions with industrial importance.

Automation of Large-Scale Gaseous Ozonation: A Case Study of Textile and PPE Decontamination

There is an ever-growing need in several industries to disinfect or sanitise products (i.e., to reduce or eliminate pathogenic microorganisms from their surfaces). Gaseous ozone has been widely applied for this purpose, particularly during the era of the COVID-19 pandemic. However, the large-scale deployment of this technology usually involves a manually-operated chamber, into which articles are loaded and subsequently unloaded after treatment—a batch process. Although the development of large-scale, automated and continuous ozonation equipment has hardly been reported in the literature, this has tremendous potential for industries seeking to decontaminate certain articles/products in a rapid and effective manner. In this paper, an overview of the design and implementation considerations for such an undertaking is evaluated. By presenting a case study for a developed automated system for clothing and personal protective equipment (PPE) disinfection, we provide key data regarding the automation procedure/design’s considerations, risks, material compatibility, safety, sustainability and process economics. Our analysis shows that the transfer time for garments between successive chambers and the agility of the sliding doors are crucial to achieving the desired throughput. The automated system is capable of effectively treating (20 ppm ozone for 4 min) 20,000 garments within an 8-h shift, based on a transfer time of 2 min and a sliding door speed of 0.4 m/s. The flexibility of the system allows for variation in the concentration or exposure time, depending on the contamination level and the consequent decontamination efficiency desired. This flexibility significantly limits the degradation of the material during treatment. A return on investment of 47% is estimated for this novel system.

Filtration performance, fit test and side effects of respiratory personal protective equipment following decontamination: Observations for user safety and comfort.

While facing personal protective equipment (PPE) shortages during the COVID-19 pandemic, several institutions looked to PPE decontamination and reuse options. This study documents the effect of two hydrogen peroxide treatments on filtration efficiency and fit tests as well as the side effects for volunteers after the decontamination of N95 filtering facepiece respirators (FFRs). We also propose an efficient and large-scale treatment protocol that allows for the traceability of this protective equipment in hospitals during PPE shortages. The effects of low-temperature hydrogen peroxide sterilization and hydrogen peroxide vapor (HPV) on two FFR models (filtration, decontamination level, residual emanation) were evaluated. Ten volunteers reported comfort issues and side effects after wearing 1h FFRs worn and decontaminated up to five times. The decontamination process does not negatively affect FFR efficiency, but repeated use and handling tend to lead to damage, limiting the number of times FFRs can be reused. Moreover, the recommended 24-h post-treatment aeration does not sufficiently eliminate residual hydrogen peroxide. Prolonged aeration time increased user comfort when using decontaminated FFRs. HPV and low-temperature hydrogen peroxide sterilization seem to be appropriate treatments for FFR decontamination when the PPE is reused by the same user. PPE decontamination and reuse methods should be carefully considered as they are critical for the comfort and safety of healthcare workers.

Perception of Professionals from Different Healthcare Units Regarding the Use of Spray Technology for the Instantaneous Decontamination of Personal Protective Equipment during the Coronavirus Disease Pandemic: A Short Analysis

Within the context of the coronavirus disease (COVID-19) pandemic, different disinfection technologies have been developed to efficiently exercise microbial control, especially to minimize the potential risks that are associated with transmission and infection among healthcare professionals. Thus, the aim of this work was to evaluate the perception of professionals regarding the use of a new technology (chamber) for the instantaneous decontamination of personal protective equipment before the doffing stage. This was a cross-sectional descriptive study where the study data were obtained by using a questionnaire with qualitative questions. In total, 245 professionals participated in the study in three hospitals. Healthcare professionals represented 72.24% (n = 177) of the investigated sample. Approximately 69% of the professionals considered the disinfection chamber as a safe technology, and 75.10% considered it as an important and effective protective barrier for healthcare professionals in view of its application before the doffing process. The results found in this study demonstrate that the use of spray technology in the stage prior to the doffing process is acceptable to professionals, and that it can be an important tool for ensuring the additional protection of the professionals who work directly with patients who are diagnosed with COVID-19.

Methylene blue applied to N95 respirators and medical masks for SARS-CoV-2 decontamination: What is the likelihood of inhaling methylene blue?

BackgroundGlobal shortage of personal protective equipment (PPE), as consequence of the COVID-19 global pandemic, has unmasked significant resource inequities prompting efforts to develop methods for safe PPE decontamination for reuse. The World Health Organization (WHO) in their Rational Use of PPE bulletin cited the use of a photodynamic dye, methylene blue, and light exposure as a viable option for N95 respirator decontamination. Because WHO noted that methylene blue (MB) would be applied to surfaces through which health care workers breathe, we hypothesized that little to no MB will be detectable by spectroscopy when the PPE is subjected to MB at supraphysiologic airflow rates.MethodsA panel of N95 respirators, medical masks, and cloth masks were sprayed with 5 cycles of 1,000 uM MB solution. Mask coupons were subjected to the equivalent of 120 L/min of 100% humidified air flow. Effluent gas was trapped in an aqueous solution and the resultant fluid was sampled for MB absorbance with a level of detection of 0.004 mg/m3.ResultsNo detectable MB was identified for any mask using Ultraviolet-Visible spectroscopy.ConclusionsAt 500-fold the amount of MB applied to N95 respirators and medical masks as were used for the decontamination study cited in the WHO Rational Use of PPE bulletin, no detectable MB was observed, thus providing safety evidence for the use of methylene blue and light exposure for mask decontamination.

Efficacy and self-similarity of SARS-CoV-2 thermal decontamination

Dry heat decontamination has been shown to effectively inactivate viruses without compromising the integrity of delicate personal protective equipment (PPE), allowing safe reuse and helping to alleviate shortages of PPE that have arisen due to COVID-19. Unfortunately, current thermal decontamination guidelines rely on empirical data which are often sparse, limited to a specific virus, and unable to provide fundamental insight into the underlying inactivation reaction. In this work, we experimentally quantified dry heat decontamination of SARS-CoV-2 on disposable masks and validated a model that treats the inactivation reaction as thermal degradation of macromolecules. Furthermore, upon nondimensionalization, all of the experimental data collapse onto a unified curve, revealing that the thermally driven decontamination process exhibits self-similar behavior. Our results show that heating surgical masks to 70 °C for 5 min inactivates over 99.9% of SARS-CoV-2. We also characterized the chemical and physical properties of disposable masks after heat treatment and did not observe degradation. The model presented in this work enables extrapolation of results beyond specific temperatures to provide guidelines for safe PPE decontamination. The modeling framework and self-similar behavior are expected to extend to most viruses—including yet-unencountered novel viruses—while accounting for a range of environmental conditions.

UV decontamination of personal protective equipment with idle laboratory biosafety cabinets during the COVID-19 pandemic

Personal protective equipment (PPE) is crucially important to the safety of both patients and medical personnel, particularly in the event of an infectious pandemic. As the incidence of Coronavirus Disease 2019 (COVID-19) increases exponentially in the United States and many parts of the world, healthcare provider demand for these necessities is currently outpacing supply. In the midst of the current pandemic, there has been a concerted effort to identify viable ways to conserve PPE, including decontamination after use. In this study, we outline a procedure by which PPE may be decontaminated using ultraviolet (UV) radiation in biosafety cabinets (BSCs), a common element of many academic, public health, and hospital laboratories. According to the literature, effective decontamination of N95 respirator masks or surgical masks requires UV-C doses of greater than 1 Jcm-2, which was achieved after 4.3 hours per side when placing the N95 at the bottom of the BSCs tested in this study. We then demonstrated complete inactivation of the human coronavirus NL63 on N95 mask material after 15 minutes of UV-C exposure at 61 cm (232 μWcm-2). Our results provide support to healthcare organizations looking for methods to extend their reserves of PPE.

Potential application of novel technology developed for instant decontamination of personal protective equipment before the doffing step.

The use of personal protective equipment (PPE) has been considered the most effective way to avoid the contamination of healthcare workers by different microorganisms, including SARS-CoV-2. A spray disinfection technology (chamber) was developed, and its efficacy in instant decontamination of previously contaminated surfaces was evaluated in two exposure times. Seven test microorganisms were prepared and inoculated on the surface of seven types of PPE (respirator mask, face shield, shoe, glove, cap, safety glasses and lab coat). The tests were performed on previously contaminated PPE using a manikin with a motion device for exposure to the chamber with biocidal agent (sodium hypochlorite) for 10 and 30s. In 96.93% of the experimental conditions analyzed, the percentage reduction was >99% (the number of viable cells found on the surface ranged from 4.3x106 to <10 CFU/mL). The samples of E. faecalis collected from the glove showed the lowest percentages reduction, with 86.000 and 86.500% for exposure times of 10 and 30 s, respectively. The log10 reduction values varied between 0.85 log10 (E. faecalis at 30 s in glove surface) and 9.69 log10 (E. coli at 10 and 30 s in lab coat surface). In general, E. coli, S. aureus, C. freundii, P. mirabilis, C. albicans and C. parapsilosis showed susceptibility to the biocidal agent under the tested conditions, with >99% reduction after 10 and 30s, while E. faecalis and P. aeruginosa showed a lower susceptibility. The 30s exposure time was more effective for the inactivation of the tested microorganisms. The results show that the spray disinfection technology has the potential for instant decontamination of PPE, which can contribute to an additional barrier for infection control of healthcare workers in the hospital environment.

PPE decontamination to overcome PPE shortage in rural area during pandemic

SummaryDespite remarkable developments in healthcare, the world was not ready to stop the spread of the novel COVID-19 pandemic almost a century after the great influenza pandemic. The explosive increase in the number of patients stalled the healthcare system, and the first and apparent issue was the shortage of personal protective equipment (PPE). Our group established a system using a hydrogen peroxide vaporization method to decontaminate and reuse N95 respirators for healthcare workers. The system decontaminated over 12,000 units of PPE to cover institutions in West Texas. This service provided support at the most needed time during the pandemic.

An international survey of healthcare workers use of personal protective equipment during the early stages of the COVID-19 pandemic.

ObjectiveLittle is known regarding the specific ways personal protective equipment (PPE) has been used and reused during the coronavirus disease 2019 (COVID‐19) pandemic. The objective of this study was to evaluate the patterns of PPE use and the impact of PPE availability on the attitudes and well‐being of an international population of healthcare workers.MethodsThis was an online, cross‐sectional survey of healthcare workers. The survey was disseminated internationally using social media, specialty society list‐serves, and email augmented by snowball sampling to healthcare workers who provided direct care to patients with suspected or confirmed COVID‐19. The survey was conducted between April 13 and May 1, 2020. The primary outcome was self‐reported PPE use during aerosol‐generating medical procedures. Other outcomes included PPE use during care for respiratory patients in general, PPE reuse, PPE decontamination, and healthcare worker impressions related to their work and the pandemic.ResultsA total of 2227 healthcare workers from 23 countries completed the survey. The N95 was the most common respirator among the 1451 respondents who performed aerosol‐generating procedures (n = 1050, 72.3%). Overall, 1783 (80.1%) of providers reported general reuse of PPE, which was similar across US regions but less common in Canada, Italy, and Spain. The most commonly reused item of PPE was the N95 respirator, with the majority of respondents who reused PPE reporting N95 reuse (n = 1157, 64.9%). Of the 1050 individuals who wore an N95 mask while performing an aerosol‐generating medical procedure, 756 (72%) reported re‐using an N95, and 344 (45.5%) reported reuse for >3 days. Qualitative results identified several common themes, including (1) lack of availability of PPE, (2) fear and anxiety as a result of inadequate PPE, (3) potential exposure to family members, and (4) concerns regarding workload and pay.ConclusionsThis international survey of healthcare workers found that N95 respirators were commonly used to care for patients with respiratory symptoms with and without aerosol‐generating medical procedures. Healthcare workers reported an unprecedented need to reuse PPE that was designed for single‐use, specifically the N95 respirator. The reuse of PPE increased the perceived risk for COVID‐19 infection and harmed mental health.

Decontaminating N95 respirators during the COVID-19 pandemic: simple and practical approaches to increase decontamination capacity, speed, safety and ease of use

BackgroundThe COVID-19 pandemic has caused a severe shortage of personal protective equipment (PPE), especially N95 respirators. Efficient, effective and economically feasible methods for large-scale PPE decontamination are urgently needed.Aims(1) to develop protocols for effectively decontaminating PPE using vaporized hydrogen peroxide (VHP); (2) to develop novel approaches that decrease set-up and take-down time while also increasing decontamination capacity; (3) to test decontamination efficiency for N95 respirators heavily contaminated by make-up or moisturizers.MethodsWe converted a decommissioned Biosafety Level 3 laboratory into a facility that could be used to decontaminate N95 respirators. N95 respirators were hung on metal racks, stacked in piles, placed in paper bags or covered with make-up or moisturizer. A VHP® VICTORY™ unit from STERIS was used to inject VHP into the facility. Biological and chemical indicators were used to validate the decontamination process. Findings: N95 respirators individually hung on metal racks were successfully decontaminated using VHP. N95 respirators were also successfully decontaminated when placed in closed paper bags or if stacked in piles of up to six. Stacking reduced the time needed to arrange N95 respirators for decontamination by approximately two-thirds while almost tripling facility capacity. Make-up and moisturizer creams did not interfere with the decontamination process.ConclusionsRespirator stacking can reduce the hands-on time and increase decontamination capacity. When personalization is needed, respirators can be decontaminated in labelled paper bags. Make up or moisturizers do not appear to interfere with VHP decontamination.

Monitoring SARS-CoV-2 decontamination by dry heat and ultraviolet treatment with a swine coronavirus as a surrogate

SummaryThe critical need for reliable methods to validate decontamination protocols for personal protective equipment (PPE) for re-use during the SARS-CoV-2 pandemic is limited by the need for specialized containment facilities to handle the virus. Hence, we have herein validated the use of a swine coronavirus as a surrogate, and tested the effectiveness of dry heat and ultraviolet (UV) rays for PPE decontamination. Exposure of experimentally contaminated N95 masks and hospital gowns to 60°C for 20 min, and UVC at 1800 mJ/cm2 resulted in a 4-log reduction and inactivation of the surrogate virus. This study provides a novel alternative to validate PPE reprocessing methods.

Modeling UV-C irradiation chambers for mask decontamination using Zemax OpticStudio.

Ultraviolet decontamination of personal protective equipment, particularly masks, is important in situations where mask reuse is practiced. To assist in the development of UV-C decontamination chambers, we have constructed ray tracing models in Zemax OpticStudio v20.1 for two distinct geometries, namely, a rectangular cabinet and a cylindrical can. These models provide irradiance distributions that can be used for comparison with experiment, as well as to predict local irradiance variation over the surface of a mask. In this paper we describe the model details, including: (1) a mask object in CAD format; (2) our assumptions for modeling surface properties; (3) the use of polygon object detectors for local irradiance analysis; and (4) experimental results that compare favorably to the simulations.

Uso dos Equipamentos de Proteção Individual no Atendimento Odontológico Durante Surto da COVID-19 e Alternativas em Períodos de Desabastecimento: Revisão Integrativa

Objetivo: sistematizar a produção bibliográfica sobre as recomendações para uso, uso prolongado, reuso e descontaminação de equipamentos de proteção individual (EPI) no atendimento odontológico em período de surto epidêmico de COVID-19 a partir das evidências encontradas na literatura. Material e Métodos: foi realizada uma busca bibliográfica no dia 1 de maio de 2020 em bases bibliográficas eletrônicas brasileiras e internacionais (Portal Regional da Biblioteca Virtual em Saúde, Web of Science e Pubmed), a partir da estratégia de busca (“individual protective equipment” AND “covid-19”), entre estudos publicados nos anos de 2015 a 2020. Foram também analisados documentos de órgãos de vigilância sanitária de diferentes países e recomendações da Associação Americana de Odontologia. Após aplicados os critérios de inclusão e exclusão dos documentos, 20 estudos foram considerados elegíveis para a realização da revisão. Resultados: Há uma escassez de publicações que relacionem a odontologia e o uso de EPI durante a pandemia. O uso prolongado/reuso limitado de respiradores (N95, PFF2, PFF3) pode ser recomendado em períodos de grave desabastecimento de EPIs desde que a sua integridade e capacidade de vedação estejam mantidas. Os aventais de tecido não tecido, máscaras cirúrgicas, luvas e gorros são considerados equipamentos de uso único. Os protetores oculares podem ser reusados após limpeza e desinfecção. Conclusão: Em períodos de surtos epidêmicos da SARS-CoV-2 recomendamos para atendimento odontológico com geração de aerossol o uso de respiradores do tipo N95, PFF2, PFF3 ou equivalente, protetor facial que pode ser reusado após limpeza e desinfecção e o uso de avental impermeável, luvas e gorro que devem ser descartados a cada paciente.

Effectiveness of Ultraviolet-C Light and a High-Level Disinfection Cabinet for Decontamination of N95 Respirators.

Background:Shortages of personal protective equipment (PPE) including N95 respirators are an urgent concern in the setting of the global COVID-19 pandemic. Decontamination of PPE could be useful to maintain adequate supplies, but there is uncertainty regarding the efficacy of decontamination technologies.Methods:A modification of the American Society for Testing and Materials standard quantitative carrier disk test method (ASTM E-2197-11) was used to examine the effectiveness of 3 methods, including ultraviolet-C (UV-C) light, a high-level disinfection cabinet that generates aerosolized peracetic acid and hydrogen peroxide, and dry heat at 70°C for 30 minutes. We assessed the decontamination of 3 commercial N95 respirators inoculated with methicillin-resistant Staphylococcus aureus (MRSA) and bacteriophages MS2 and Phi6; the latter is an enveloped RNA virus used as a surrogate for coronaviruses. Three and 6 log10 reductions on respirators were considered effective for decontamination and disinfection, respectively.Results:UV-C administered as a 1-minute cycle in a UV-C box or a 30-minute cycle by a room decontamination device reduced contamination but did not meet criteria for decontamination of the viruses from all sites on the N95s. The high-level disinfection cabinet was effective for decontamination of the N95s and achieved disinfection with an extended 31-minute cycle. Dry heat at 70°C for 30 minutes was not effective for decontamination of the bacteriophages.Conclusions:UV-C could be useful to reduce contamination on N95 respirators. However, the UV-C technologies studied did not meet pre-established criteria for decontamination under the test conditions used. The high-level disinfection cabinet was more effective and met criteria for disinfection with an extended cycle.

Analysis and Assessment of Hazards Caused by Chemicals Contaminating Selected Items of Firefighter Personal Protective Equipment – a Literature Review

Aim: The aim of the presented paper is to review the literature concerning the risks related to possible contamination with chemical substances of firefighter’s personal protective equipment (i.e. special clothing, special gloves, firefighter boots and balaclavas) during rescue operations. The authors focused on contamination resulting from the interaction of aromatic and aliphatic hydrocarbons, volatile organic compounds and phthalates. Introduction: During rescue operations, firefighters are exposed to chemicals which are inherent in fires in buildings and open spaces. The health hazards caused by chemicals accumulating on the surface of personal protective equipment, which can enter the firefighter’s body through the skin, posing a lethal threat, is becoming an increasingly recognized issue. Scientific research shows that chemicals generated during fires are harmful – a significant proportion of them has a confirmed carcinogenic and mutagenic effect. Methodology: The presented analysis of the issue of chemical contamination of personal protective equipment and the associated risks to the firefighter was prepared on the basis of a review of selected Polish and foreign literature. The main types of chemical pollutants with chemical substances and the determined levels of pollution were addressed in the paper, indicating the conditions under which they were obtained. Additionally, the properties of the most common groups of chemicals that contaminate personal protective equipment are described. The characteristics of firefighter’s personal protective equipment, with the particular focus on the materials used for special firefighter suit, are also presented. Conclusions: A review of relevant literature indicates that contamination of firefighter’s personal protective equipment were investigated mainly with respect to the presence of aromatic and aliphatic hydrocarbons, volatile organic compounds with a proven carcinogenic effect. Phthalates as substances posing a very high risk to fertility were less commonly studied. The high content of harmful chemicals in dirt present on the surface of the material of special clothing and on other personal protective equipment, as well as in the urine metabolites, indicates unequivocally the need for decontamination of personal protective equipment after every fire.

Polycyclic aromatic hydrocarbon (PAH) and metal contamination of air and surfaces exposed to combustion emissions during emergency fire suppression: Implications for firefighters' exposures

This study examined occupational exposures of Ottawa firefighters to combustion by-products and selected metals. We measured exposures to polycyclic aromatic hydrocarbons (PAHs), antimony, cadmium, and lead using (1) personal air samplers worn by firefighters during emergency fire suppression; (2) wipe samples from skin, personal clothing, and personal protective equipment (PPE) collected before and after emergency firefighting (n = 29); and (3) air samples collected in three fire stations vehicle bays, truck cabs, and one administration office. We assessed OFS PPE decontamination procedures using wipe samples collected before and after laundering (n = 12). Air concentrations exceeded occupational exposure limits at two fire events for lead and nine for PAHs. After fire suppression, PAH concentrations were significantly higher on skin and PPE (p < 0.001), skin, clothing, and PPE for antimony (p < 0.001, 0.01, and 0.05, respectively), and skin and PPE for lead (p < 0.001). Air concentrations of PAHs and antimony were significantly higher in vehicle bays compared to the office (p < 0.05), but significantly lower compared to fire truck cabs (p < 0.05). Washing PPE was effective in removing, on average, 61% of PAHs, 55% of antimony, 97% of lead, and 90% of cadmium. These results indicate that firefighters are significantly exposed, via multiple routes, to combustion by-products during on-shift fire suppression.

Decontamination of Personal Protective Equipment

Exploratory field analyses of the inactivation capacity of disinfectants on contaminated personal protective equipment (PPE) are required to select a suitable surrogate for biohazardous agents like spores of Bacillus anthracis. The objectives of our study were (1) the determination of an appropriate surrogate for the inactivation of spores of B. anthracis with peracetic acid (PAA), and (2) application of optimized inactivation conditions for an effective decontamination of PPE with PAA under field conditions. For inactivation studies, B. anthracis spores from different strains and B. thuringiensis spores were fixed by air drying on carriers prepared from PPE fabric. Time and concentration studies with PAA-based disinfectants revealed that the spores of the B. thuringiensis strain DSM 350 showed an inactivation profile comparable to that of the spores of the B. anthracis strain with the highest stability, implying that B. thuringiensis can serve as an appropriate surrogate. Rapid (3 to 5 minutes) and effective surface decontamination was achieved with 2% PAA/0.2% surfactant. In field studies, PPE contaminated with spores of B. thuringiensis was treated with the disinfectant. Optimizing the decontamination technique revealed that spraying in combination with brushing was effective within 5 minutes of exposure.