Objective To evaluate the performance of vaporized hydrogen peroxide （VHP） for the bio-decontamination of the high efficiency particulate air （HEPA） filter unit. Methods Self-made or commercially available bioindi...Objective To evaluate the performance of vaporized hydrogen peroxide （VHP） for the bio-decontamination of the high efficiency particulate air （HEPA） filter unit. Methods Self-made or commercially available bioindicators were placed at designated locations in the HEPA filter unit under VHP fumigation. The spores on coupons were then extracted by 0.5 h submergence in eluent followed by 200- time violent knocks. Results Due to the presence of HEPA filter in the box, spore recovery from coupons placed at the bottom of the filter downstream was significantly higher than that from coupons placed at the other locations. The gap of decontamination efficiency between the top and the bottom of the filter downstream became narrower with the exposure time extended. The decontamination efficiency of the bottom of the filter downstream only improved gently with the injection rate of H202 increased and the decontamination efficiency decreased instead when the injection rate exceeded 2.5 g/min. The commercially available bioindicators were competent to indicate the disinfection efficiency of VHP for the HEPA filter unit. Conclusion The HEPA filter unit is more difficult than common enclosure to decontaminate using VHP fumigation. Complete decontamination can be achieved by extending fumigation time. VHP fumigation can be applied for in-situ biodecontamination of the HEPA filter unit as an alternative method to formaldehyde fumigation.展开更多
Concerns have been raised about both the disinfection and the reusability of respiratory protective equipment following a disinfection process.Currently,there is little data available on the effects of disinfection an...Concerns have been raised about both the disinfection and the reusability of respiratory protective equipment following a disinfection process.Currently,there is little data available on the effects of disinfection and decontamination on positive pressure respiratory protective hoods(PPRPH).In this study,we evaluated the effect of vaporized hydrogen peroxide(VHP)on the disinfection of PPRPH to determine applicability of this method for disinfection of protective equipment,especially protective equipment with an electric supply system.A hydrogen peroxide-based fumigation sterilization cabinet was developed particularly for disinfection of protective equipment,and the disinfection experiments were conducted using four PPRPHs hung in the fumigation chamber.The pathogenic microorganism Geobacillus stearothermophilus ATCC 7953 was used as a biological indicator in this study and the relationship between air flow(the amount of VHP)and disinfection was investigated.Both function and the material physical properties of the PPRPH were assessed following the disinfection procedure.No surviving Geobacillus stearothermophilus ATCC 7953,both inside and outside of these disinfected PPRPHs,could be observed after a 60 min treatment with an air flow of 10.5–12.3 m^(3)/h.Both function and material physical properties of these PPRPHs met the working requirements after disinfection.This study indicates that air flow in the fumigation chamber directly influences the concentration of VHP.The protective equipment fumigation sterilization cabinet developed in this paper achieves the complete sterilization of the PPRPHs when the air flow is at 10.5–12.3 m^(3)/h,and provides a potential solution for the disinfection of various kind of protective equipment.展开更多
Biosafety equipment is the key barrier enabling high containment laboratories to handle high risk agents that may cause serious and potentially lethal infections. This perspective thoroughly analyzes the development o...Biosafety equipment is the key barrier enabling high containment laboratories to handle high risk agents that may cause serious and potentially lethal infections. This perspective thoroughly analyzes the development of many kinds of key biosafety technologies, and equipment for protection of laboratory workers and for high containment laboratory facilities in China. Over more than ten years of rapid development, China has had remarkable achievements in key biosafety technologies and equipment in high containment laboratories. These technologies basically meet the needs of high containment laboratories construction in China. Furthermore, according to the current global situation regarding the prevention and control of infectious diseases and the technical development level of biosafety equipment, this paper proposes targeted suggestions and notes that China still needs to increase investment in scientific research to provide further technical and equipment support enabling us to build a community with a bright future in terms of human biosafety.展开更多
Fast and accurate prediction of particle transport is essential for the determination of as-needed mitigation strategies to improve indoor air quality.Several methods have been proposed to achieve this goal.However,th...Fast and accurate prediction of particle transport is essential for the determination of as-needed mitigation strategies to improve indoor air quality.Several methods have been proposed to achieve this goal.However,they mainly based on the Reynolds-averaged Navier-Stokes(RANS)approach,which may affect the accuracy of particle calculations.Considering the lattice Boltzmann method(LBM)can execute high-speed large eddy simulation(LES)while Markov chain model performs well for particle calculations.This study proposed an LBM-LES-Markov-chain framework for indoor transient particle transport simulation.The performance of the proposed framework was investigated in a two-zone ventilated chamber,and compared to the CFD-LES based models.Results show that the proposed framework is as accurate as but faster than the CFD-LES based models.The mean normalized root-mean-square deviations of the proposed model is 12%,similar to the CFD-LES-Lagrangian(15%)and CFD-LES-Eulerian(13%)models.The computing time of the proposed model is 5.66 h,shorter than the CFD-LES-Lagrangian(153 h)and CFD-LES-Eulerian(15.03 h)models.Furthermore,we further compared the framework with CFD-RNG based Markov chain model,CFD-RANS based models,and FFD-Markov-chain model and found that it is an alternative for the fast prediction of indoor particle concentration.展开更多
Humanity has been facing the threat of a variety of ifectious diseases.Airborne microorganisms can cause airbome infectious diseases,which spread rapidly and extensively,causing huge losscs to human society on a globa...Humanity has been facing the threat of a variety of ifectious diseases.Airborne microorganisms can cause airbome infectious diseases,which spread rapidly and extensively,causing huge losscs to human society on a global scale.In recent years,the detection technology for airbome microorganisms has developed rapidly;it can be roughly divided into biochemical,immune,and molecular technologies.However,these technologies still have some shortcomings;they are time consuming and have low sensitivity and poor stability.Most of them need to be used in the ideal environment of a laboratory,which limits their applications.A biosensor is a device that converts biological signals into detectable signals.As an interdisciplinary feld,biosensors have successfully introduced a variety of technologies for bio-detection.Given their fast analysis speed,high sensitivity good portability,strong specifcity,and low cost,biosensors have been widely uised in cnvironmental monitoring,medical research,food and agricultural safety,military.medicine and other fields.In recent years,the performance of biosensors has greatly improved,becoming.a promising techmology for airborne microorganism detection.This review introduces the detection principle of biosensors from the three aspects of component identification,energy conversion principle,and signal amplification.It also summarizes its research and application in airborne microorganism detection.The new progress and future development trend of the biosensor detection of airbormne microorganisms are analyzed.展开更多
The positive pressure biological protective suit is the highest degree of personal protective equipment,and its performance directly impacts the health and safety of the wearer.Protection factor is the most critical m...The positive pressure biological protective suit is the highest degree of personal protective equipment,and its performance directly impacts the health and safety of the wearer.Protection factor is the most critical measure of the performance of a positive pressure bio-protective suit.This study establishes a dynamic detection system for the positive pressure bio-protective suit,to evaluate its safety risks,and explores methods to reduce these risks.A manikin was used to perform human actions,such as raising the arms,sitting,and walking,that were simulated at different levels.Integrity breaches of different shapes and sizes were made to different parts of the suit for evaluation.The aerosol concentration and the pressure of the suit were detected.Positive-pressure suits provide exceptionally good protection even in accident scenarios and provide a greater flexibility and more ergonomic benefits.However,sufficiently large(>3 cm)breaches caused a negative-pressure and an inward airflow during vigorous activities.The location of the breach site on the suit also had a significant effect on bio-aerosol leakage.Studies have shown that effective methods to avoid the risk of damage include increasing the air supply flow and performing gentle movements while wearing the suit.The dynamic detection method and the results obtained in this study are a significant advance to predict and avoid the risks associated with powered air-purifying suits.展开更多
Objective:Trying to establish the key technical indicators related to positive pressure biological protective clothing(PPBPC),providing technical support for the establishment of PPBPC standards in the future.Method:W...Objective:Trying to establish the key technical indicators related to positive pressure biological protective clothing(PPBPC),providing technical support for the establishment of PPBPC standards in the future.Method:We examined the protection standard systems established by the major standards organizations in China and other developed countries.We also analyzed the technical indicators of the gas-tight chemical protective clothing and ventilated protective clothing against particulate radioactive contamination which closely related to PPBPC.And tested the performance of a set of imported dual-purpose PPBPC to verify the fit of its technical indicators with the standards.We aimed to identify the status of China’s standards in the area of personnel protection and put forward feasible suggestions for the production of PPBPC in China.Results:Developed countries in Europe and North America have a complete system of standard protective clothing.China should also strengthen the construction of standard protective clothing,especially PPBPC.Conclusion:With the improvements in infectious disease prevention and control on a global scale,the demand for PPBPC continues to increase and consideration should be given to the establishment of standards for this.展开更多
Objective:Airtightness of containment structures of a high-level biosafety laboratory is a critical parameter for preventing leakage of harmful bioaerosols.The aim of this study is to investigate the sealing technolog...Objective:Airtightness of containment structures of a high-level biosafety laboratory is a critical parameter for preventing leakage of harmful bioaerosols.The aim of this study is to investigate the sealing technology of stainless steel structural airtight biosafety containment facilities.Methods:An experimental study was conducted on a domestic high-level pathogenic microorganism model laboratory,considering the sealing process of the containment structure,including airtight doors,pass boxes,dunk tanks,through-wall pipeline sealing devices,and sealed floor drains.Results:The results indicate that the airtightness of the model laboratory containment structure meets the tightness requirements of a biosafety level-4(BSL-4)laboratory.They also indicate that the construction technology of stainless steel enclosure structures used by the laboratory and the tightness performance and installation process of the developed airtight protective equipment meet the technical requirements of a BSL-4 laboratory.Conclusions:This successful model laboratory indicates that China has the research and development capacity for stainless steel airtight containment structure manufacturing processes,airtight protective equipment,and technical capacity for independent construction of the highest-level pathogenic microorganism laboratories.展开更多
Positive Pressure Protective Clothing(PPPC)is the most important personal protective equipment for BSL-4 laboratory and a primary barrier to avoid exposure to pathogenic microorganisms.However,during the process of st...Positive Pressure Protective Clothing(PPPC)is the most important personal protective equipment for BSL-4 laboratory and a primary barrier to avoid exposure to pathogenic microorganisms.However,during the process of storage,utilization,disinfection and inspection,it will be inevitable damaged in varying degrees.PPPC is expensive;therefore,effective repairs become an important procedure to prolong service life of PPPC and to ensure their protective function.This paper analyzed those common damages in PPPC during routine BSL-4 laboratory operations and provided repair plans which can be used as references for users and maintenance personnel.展开更多
基金supported by the Research Fund from the Ministry of Science and Technology of the People’s Republic of China, 2009ZX10004-502 and 2009ZX10004-709
文摘Objective To evaluate the performance of vaporized hydrogen peroxide （VHP） for the bio-decontamination of the high efficiency particulate air （HEPA） filter unit. Methods Self-made or commercially available bioindicators were placed at designated locations in the HEPA filter unit under VHP fumigation. The spores on coupons were then extracted by 0.5 h submergence in eluent followed by 200- time violent knocks. Results Due to the presence of HEPA filter in the box, spore recovery from coupons placed at the bottom of the filter downstream was significantly higher than that from coupons placed at the other locations. The gap of decontamination efficiency between the top and the bottom of the filter downstream became narrower with the exposure time extended. The decontamination efficiency of the bottom of the filter downstream only improved gently with the injection rate of H202 increased and the decontamination efficiency decreased instead when the injection rate exceeded 2.5 g/min. The commercially available bioindicators were competent to indicate the disinfection efficiency of VHP for the HEPA filter unit. Conclusion The HEPA filter unit is more difficult than common enclosure to decontaminate using VHP fumigation. Complete decontamination can be achieved by extending fumigation time. VHP fumigation can be applied for in-situ biodecontamination of the HEPA filter unit as an alternative method to formaldehyde fumigation.
基金funding projects of Chinese Ministry of Science and Technology:National Key research and development plan of China(2016YFC1201404)the Megaproject for Infectious Disease Research of China(2017ZX10304403-004-001).
文摘Concerns have been raised about both the disinfection and the reusability of respiratory protective equipment following a disinfection process.Currently,there is little data available on the effects of disinfection and decontamination on positive pressure respiratory protective hoods(PPRPH).In this study,we evaluated the effect of vaporized hydrogen peroxide(VHP)on the disinfection of PPRPH to determine applicability of this method for disinfection of protective equipment,especially protective equipment with an electric supply system.A hydrogen peroxide-based fumigation sterilization cabinet was developed particularly for disinfection of protective equipment,and the disinfection experiments were conducted using four PPRPHs hung in the fumigation chamber.The pathogenic microorganism Geobacillus stearothermophilus ATCC 7953 was used as a biological indicator in this study and the relationship between air flow(the amount of VHP)and disinfection was investigated.Both function and the material physical properties of the PPRPH were assessed following the disinfection procedure.No surviving Geobacillus stearothermophilus ATCC 7953,both inside and outside of these disinfected PPRPHs,could be observed after a 60 min treatment with an air flow of 10.5–12.3 m^(3)/h.Both function and material physical properties of these PPRPHs met the working requirements after disinfection.This study indicates that air flow in the fumigation chamber directly influences the concentration of VHP.The protective equipment fumigation sterilization cabinet developed in this paper achieves the complete sterilization of the PPRPHs when the air flow is at 10.5–12.3 m^(3)/h,and provides a potential solution for the disinfection of various kind of protective equipment.
基金This work was supported by the National Key Research and Develop-ment Program of China(2018YFC1200300).
文摘Biosafety equipment is the key barrier enabling high containment laboratories to handle high risk agents that may cause serious and potentially lethal infections. This perspective thoroughly analyzes the development of many kinds of key biosafety technologies, and equipment for protection of laboratory workers and for high containment laboratory facilities in China. Over more than ten years of rapid development, China has had remarkable achievements in key biosafety technologies and equipment in high containment laboratories. These technologies basically meet the needs of high containment laboratories construction in China. Furthermore, according to the current global situation regarding the prevention and control of infectious diseases and the technical development level of biosafety equipment, this paper proposes targeted suggestions and notes that China still needs to increase investment in scientific research to provide further technical and equipment support enabling us to build a community with a bright future in terms of human biosafety.
文摘Fast and accurate prediction of particle transport is essential for the determination of as-needed mitigation strategies to improve indoor air quality.Several methods have been proposed to achieve this goal.However,they mainly based on the Reynolds-averaged Navier-Stokes(RANS)approach,which may affect the accuracy of particle calculations.Considering the lattice Boltzmann method(LBM)can execute high-speed large eddy simulation(LES)while Markov chain model performs well for particle calculations.This study proposed an LBM-LES-Markov-chain framework for indoor transient particle transport simulation.The performance of the proposed framework was investigated in a two-zone ventilated chamber,and compared to the CFD-LES based models.Results show that the proposed framework is as accurate as but faster than the CFD-LES based models.The mean normalized root-mean-square deviations of the proposed model is 12%,similar to the CFD-LES-Lagrangian(15%)and CFD-LES-Eulerian(13%)models.The computing time of the proposed model is 5.66 h,shorter than the CFD-LES-Lagrangian(153 h)and CFD-LES-Eulerian(15.03 h)models.Furthermore,we further compared the framework with CFD-RNG based Markov chain model,CFD-RANS based models,and FFD-Markov-chain model and found that it is an alternative for the fast prediction of indoor particle concentration.
基金by the National Natural Science Foundation of China(Grant No.51678402)the Tianjin New Crown Epidemic Emergency Project(No.20ZXGBSY00100).
文摘Humanity has been facing the threat of a variety of ifectious diseases.Airborne microorganisms can cause airbome infectious diseases,which spread rapidly and extensively,causing huge losscs to human society on a global scale.In recent years,the detection technology for airbome microorganisms has developed rapidly;it can be roughly divided into biochemical,immune,and molecular technologies.However,these technologies still have some shortcomings;they are time consuming and have low sensitivity and poor stability.Most of them need to be used in the ideal environment of a laboratory,which limits their applications.A biosensor is a device that converts biological signals into detectable signals.As an interdisciplinary feld,biosensors have successfully introduced a variety of technologies for bio-detection.Given their fast analysis speed,high sensitivity good portability,strong specifcity,and low cost,biosensors have been widely uised in cnvironmental monitoring,medical research,food and agricultural safety,military.medicine and other fields.In recent years,the performance of biosensors has greatly improved,becoming.a promising techmology for airborne microorganism detection.This review introduces the detection principle of biosensors from the three aspects of component identification,energy conversion principle,and signal amplification.It also summarizes its research and application in airborne microorganism detection.The new progress and future development trend of the biosensor detection of airbormne microorganisms are analyzed.
基金Thanks for the two funding projects of Chinese Ministry of Science and Technology:the Megaproject for Infectious Disease Research of China:2017ZX10304403-004the National High Technology Research and Development Program of China:2014AA021405.
文摘The positive pressure biological protective suit is the highest degree of personal protective equipment,and its performance directly impacts the health and safety of the wearer.Protection factor is the most critical measure of the performance of a positive pressure bio-protective suit.This study establishes a dynamic detection system for the positive pressure bio-protective suit,to evaluate its safety risks,and explores methods to reduce these risks.A manikin was used to perform human actions,such as raising the arms,sitting,and walking,that were simulated at different levels.Integrity breaches of different shapes and sizes were made to different parts of the suit for evaluation.The aerosol concentration and the pressure of the suit were detected.Positive-pressure suits provide exceptionally good protection even in accident scenarios and provide a greater flexibility and more ergonomic benefits.However,sufficiently large(>3 cm)breaches caused a negative-pressure and an inward airflow during vigorous activities.The location of the breach site on the suit also had a significant effect on bio-aerosol leakage.Studies have shown that effective methods to avoid the risk of damage include increasing the air supply flow and performing gentle movements while wearing the suit.The dynamic detection method and the results obtained in this study are a significant advance to predict and avoid the risks associated with powered air-purifying suits.
基金This work was supported by Major infectious diseases such as AIDS and viral hepatitis prevention and control of major projects(2017ZX10304403-004)the National Key Research and Development Program of China(2016YFC1201405).
文摘Objective:Trying to establish the key technical indicators related to positive pressure biological protective clothing(PPBPC),providing technical support for the establishment of PPBPC standards in the future.Method:We examined the protection standard systems established by the major standards organizations in China and other developed countries.We also analyzed the technical indicators of the gas-tight chemical protective clothing and ventilated protective clothing against particulate radioactive contamination which closely related to PPBPC.And tested the performance of a set of imported dual-purpose PPBPC to verify the fit of its technical indicators with the standards.We aimed to identify the status of China’s standards in the area of personnel protection and put forward feasible suggestions for the production of PPBPC in China.Results:Developed countries in Europe and North America have a complete system of standard protective clothing.China should also strengthen the construction of standard protective clothing,especially PPBPC.Conclusion:With the improvements in infectious disease prevention and control on a global scale,the demand for PPBPC continues to increase and consideration should be given to the establishment of standards for this.
基金This study was supported by the National Key Research And Development Program,China(2016YFC1201403).
文摘Objective:Airtightness of containment structures of a high-level biosafety laboratory is a critical parameter for preventing leakage of harmful bioaerosols.The aim of this study is to investigate the sealing technology of stainless steel structural airtight biosafety containment facilities.Methods:An experimental study was conducted on a domestic high-level pathogenic microorganism model laboratory,considering the sealing process of the containment structure,including airtight doors,pass boxes,dunk tanks,through-wall pipeline sealing devices,and sealed floor drains.Results:The results indicate that the airtightness of the model laboratory containment structure meets the tightness requirements of a biosafety level-4(BSL-4)laboratory.They also indicate that the construction technology of stainless steel enclosure structures used by the laboratory and the tightness performance and installation process of the developed airtight protective equipment meet the technical requirements of a BSL-4 laboratory.Conclusions:This successful model laboratory indicates that China has the research and development capacity for stainless steel airtight containment structure manufacturing processes,airtight protective equipment,and technical capacity for independent construction of the highest-level pathogenic microorganism laboratories.
基金This work was supported by Major Infectious Diseases such as AIDS and Viral Hepatitis Prevention and Control of Major Projects(2017ZX10304403-004)。
文摘Positive Pressure Protective Clothing(PPPC)is the most important personal protective equipment for BSL-4 laboratory and a primary barrier to avoid exposure to pathogenic microorganisms.However,during the process of storage,utilization,disinfection and inspection,it will be inevitable damaged in varying degrees.PPPC is expensive;therefore,effective repairs become an important procedure to prolong service life of PPPC and to ensure their protective function.This paper analyzed those common damages in PPPC during routine BSL-4 laboratory operations and provided repair plans which can be used as references for users and maintenance personnel.
