Volatile Organic Chemical Risk Analysis for Biosafety Cabinets (BSCs) 27 Jul 2022, 1:27 pm

Canopy-connected Type A2 BSCs can handle most quantities of volatile chemicals used in biomedical research, in my opinion.

Scroll to the bottom to get formulas to calculate acceptable quantities of volatile chemicals in BSCs from The Baker Company: 

Statements from NSF/ANSI 49 – 2020 Informative Annex 1: Biosafety cabinet selection, installation, lifespan and decommissioning. 
© 2021 NSF: This document is publically available at no cost.

https://www.techstreet.com/nsf/standards/nsf-ansi-49-2020-annex-i-1?product_id=2221312

I-1.3.1.3 Question three: What types and quantities of chemical vapors will be generated in the BSC?

As important as the preceding question, the user must also foresee the types and quantities of chemical vapors that will be generated in the cabinet. Because chemical vapors can freely pass through HEPA/ULPA filters, both Class I and Class II BSCs must be exhausted out of the laboratory when used with these types of chemicals. For the Class II BSCs, Types B1 and B2 must be direct connected to an external exhaust system in order to operate properly; Types A1, A2, and C1 can be converted to operate in either a canopy ducted or recirculating mode, depending on the users’ requirements. The airflow patterns of Types A1, A2, B1, B2 and C1 BSCs are shown in Figures 35, 37, 38 and 40, respectively.

Class II BSCs typically do not feature explosion-proof electrical components in their total work area or internally. Therefore, use of flammable or explosive materials in quantities above their explosive limit are not recommended.

Types of chemicals used in cabinet should be considered as some can destroy the filter medium, housings and gaskets causing loss of containment.

The percentage of air in the total work area that is recirculated within the BSC versus exhausted varies, based on the BSC Type, subtype, and in some cases, where the chemicals are released in the total work area.

When flammable or explosive chemicals are to be used in a BSC, it is the users’ responsibility to:

— be fully cognizant with the properties of chemical(s) and the hazards associated with them;

— calculate the highest percent of recirculation that may occur in the BSC being used;

— ensure the concentration of chemical(s) released in the total work area do not exceed their explosive limit;

— utilize the lowest quantities of the chemical(s) required for the procedure being performed; and

— have appropriate spill / splash cleanup procedures in place before using the chemical(s).

Class II Biosafety Cabinet Type A1 and A2:

Work with volatile organic chemicals on the work surface permitted as an adjunct to microbiological research if the BSC is canopy-connected to external exhaust and permitted by risk analysis.

Class II Biosafety Cabinet Type C1:

Work with volatile organic chemicals on the work surface is permitted as an adjunct to microbiological research if the cabinet is connected to an exhaust system, and is acceptable after performing a risk analysis. Typically, a majority of the downflow air is directly exhausted from the center portion of the cabinet.

Class II Biosafety Cabinet Type B1:

Work with volatile organic chemicals on the work surface permitted as an adjunct to microbiological research if permitted by risk analysis. A majority of the downflow air is directly exhausted from the rear portion of the cabinet.

Class II Biosafety Cabinet Type B2:

Work with volatile organic chemicals on the work surface permitted as an adjunct to microbiological research if permitted by risk analysis. All downflow air is directly exhausted from the work area with no recirculation.

In my opinion, and as stated in Annex 1 exhaust failure section; Type B2 BSCs are the most dangerous cabinets because during exhaust failure – volatile organic chemicals in the work area are dumped into the worker’s breathing zone.

Volatile Chemicals in a Class II Type A2 “Recirculated” BSCs: How Much is Safe?

Kara F. Held, Ph.D., Dan Ghidoni, Gary Hazard, and David Eagleson. Baker Company. October 2016.

https://absaconference.org/wp-content/uploads/2016/10/ABSA2016_Session12_Held.pdf

http://go.bakerco.com/VOC-webinar

Using a Class II Type A2 4-foot Baker SterilGARD with an 8” access opening for the calculations, the amount of ethanol that can be released without an explosion is 64.2 ml per minute.

(That’s a lot of volatile organic!)

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Is rain seeding cooling towers with legionella? 11 Jul 2022, 6:20 pm

A Proposal:
I suggest that public health research microbiologists study the relationship between rainfall and Legionella colonization of cooling towers / evaporative condensers leading to subsequent community acquired Legionnaires’ disease cases.

My Observations:
During research of Legionella numbers in a cooling tower published in 1985, I observed [but did not include the rainfall data] that the numbers of Legionella in the cooling tower were greater after a rain storm.
Disinfection of circulating water systems by ultraviolet light and halogenation. Richard W. Gilpin, Susan B. Dillon, Patricia Keyser, Alice Androkites, Mary Berube, Nichola Carpendale, Jane Skorina, James Hurley, and Adele M. Kaplan. 1985. Water Research. Vol. 19, Issue 7, Pages 839-848.
I have also noticed that my commercial clients sometimes have higher legionella counts in their cooling towers after significant rainfall [unpublished observations].

My Background:
After receiving a PhD in Microbiology and Public Health from Michigan State University and accepting a two-year NIH NIGMS Research Fellowship, I joined the microbiology faculty at a medical school in Philadelphia. I was involved with the investigation of the 1976 Legionnaires’ disease outbreak by collaborating with an engineering consulting company, a water treatment company, and research faculty at other medical schools in Philadelphia. I began bench research testing of environmental water samples for legionella in 1979 while collaborating with Dr. James Feeley at the Special Pathogens Laboratory, Centers for Disease Control and Prevention. I established ‘GTS Legionella Testing Service’ in 1981 and have tested thousands of samples.

Existing Publications Pointing to Rain / Legionella / Cooling Towers / Community Cases:
Publications covering rainfall delivery of Legionella to cooling towers and subsequent community cases appear to be increasing.

Extreme Precipitation and Legionnaires Disease Hospitalizations in Boston, Massachusetts from 2002-2012. Megan Kowalcyk, Varun Patel, Elizabeth Hilborn, and Timothy J. Wade. Environmental Health Perspectives.

Increased rainfall is associated with increased risk for legionellosis LA Hicks, CE Rose, BS Fields, ML Drees… – Epidemiology & …, 2007 – cambridge.org. … deficiencies in the treatment of potable water supplies must occur concurrently with heavy rains to result … If Legionella were to increase in potable water supplies after heavy rain– fall, it is … Our evidence suggests that heavy rainfall is associated with increased risk for legionellosis …

  Rainfall Is a Risk Factor for Sporadic Cases of Legionella pneumophila Pneumonia C Garcia-Vidal, M Labori, D Viasus, A Simonetti… – Plos one, 2013 – journals.plos.org… Moreover, when there is heavy rain and/or a risk of flooding, each community adopts different measures at its water purification … Our findings of a sustained rise in the number of LP cases during warm and rainy periods strongly suggest that … (2007) Increased rainfall is associated …

 The Impact of Storms on Legionella pneumophila in Cooling Tower Water, Implications for Human Health RL Brigmon, CE Turick, AS Knox… – Frontiers in …, 2020 – frontiersin.org … concentrations during this time even through exposed to similar wind and rains from the … this time of extreme weather, conditions including summer weather, high rainfall, increased humidity … in a cooling tower as a function of extreme weather conditions, including rain and wind …

  Environmental sources of community-acquired legionnaires‘ disease: A review LT Orkis, LH Harrison, KJ Mertz, MM Brooks… – International journal of …, 2018 – Elsevier … From 2000 to 2014, the reported annual rate of legionellosis in the US, which … of sporadic Legionnaires‘ disease rates by postal code, L. pneumophila and other Legionella spp … these geographic variations suggest cooling towers as a primary source of Legionnaires‘ disease in …

  Large community-acquired Legionnaires‘ disease outbreak caused by Legionella pneumophila serogroup 1, Italy, July to August 2018 M Faccini, AG Russo, M Bonini, S Tunesi… – …, 2020 – eurosurveillance.org … As reported in a recent review, warm weather, rain and higher relative humidity may have an impact on the survival of airborne Legionella, as it has been shown to survive better at a … Rainfall is a risk factor for sporadic cases of Legionella pneumophila pneumonia …

Investigation of atmospheric conditions fostering the spreading of Legionnaires‘ disease in outbreaks related to cooling towers D Villanueva, K Schepanski – International journal of biometeorology, 2019 – Springer … Legionnaires‘ disease (LD) is transmitted through the inhalation of bioaerosols from water managing devices containing Legionella pneumophila, a … found a strong correlation between
the relative humidity (RH) and the sporadic cases of legionellosis in Philadelphia …

  Ten questions concerning the aerosolization and transmission of Legionella in the built environment AJ Prussin II, DO Schwake, LC Marr – Building and environment, 2017 – Elsevier

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BSL-2 Language Urban Legends 10 Jul 2022, 11:35 am

My paper on the “+’ and “E” biosafety designations in my Documents Tab.

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COVID & Hygiene Resources 8 Jul 2022, 10:00 am

Building opening guide, including Legionnaires’ disease prevention. Consult GTS , CDC , or ASHRAE .

Johns Hopkins Coronavirus COVID-19 Map – JHU Center for Systems Science and Engineering (CSSE)

Johns Hopkins University & Medicine – COVID-19 Data Visualization Center.

Johns Hopkins University & Medicine – Coronavirus Resource Center.

CDC – Water, Sanitation, and Environmentally Related Hygiene.

CDC – COVID Website.

ASM – Latest COVID-19 Research Articles.

ASM – COVID-19 Research Registry.

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Biosafety Course at your Workplace 24 Jun 2022, 3:38 pm

The Public Control of Biohazards Course for Research & Clinical Laboratories biosafety training course in its 42nd year has ended.

Workplace courses continue.

There is no limit to the number of students. Our record at a single workplace is 300 students.

Up to 4.5 ABSA 2022 Certification Maintenance Points are available.

This is a draft course schedule that we use to negotiate the course training topics and time schedules.

This is the original US biosafety training course started at Johns Hopkins University in 1979 by Dr Byron S Tepper.
Dr Tepper and I started biosafety 101 ABSA training at the 1989 Annual Conference.
A brief resume of my qualifications is available HERE.
This course covers all elements of biosafety with hundreds of documents including hyperlinked TOCs in addition to hundreds of PowerPoint slides and instructional videos.
There are hands-on experiences with biosafety equipment and procedures and plenty of time for group problem-solving.
The course usually starts each day at 8:00 am and ends around 4-5 pm with a group discussion.
There are usually two coffee breaks, lunch, and sometimes dinner.
The workplace course usually runs for 3-43 days, depending on the training site.

Your Workplace Facilitator:
Propose a tuition cost per student with a built-in benefit for your workplace. IF you decide to charge tuition;
Provide an in-person course training site with a Windows 11 computer, projection screen, and sound system;
Receive and dispersed funds associated with your workplace expenses;
Supply RG LLC a list of course registrants [first name, last name, title, and email address] for certification purposes;
Supply each student a USB stick containing lecture and handout materials sent by RG LLC;
Make student copies of the course schedule, pre- and post-tests, course evaluation form, daily sign-in sheet, and course certificate template sent by RG LLC; and
Pay RG LLC a negotiated rate per hour for each hour of course preparation, lecture presentation, report writing, and/or on-site consulting, plus reimbursable travel and incidentals expenses.

Dr Richard W Gilpin LLC:
Provide an agreed-upon number of biosafety training and/or consulting hours;
Supply password-protected PDFs of slides/handouts for each lecture;
Brings a backup Windows 11 laptop with USB of handouts, PowerPoint slides, & videos to plug into facility Windows 11 computer, projection screen, and sound system;
Brings hands-on demonstration materials; and
Provides the course schedule, pre- and post-tests, course evaluation form, daily sign-in sheet, and course certificate template to be copied and distributed to the students.

Workplace cost for a 3 to 5-day program includes my travel expenses and a nominal fee for course preparation and direct student contact.

Lecture handouts [some over 200-pages long] with hyperlinked references have 3-deep tables of contents [TOCs].
The TOCs are hyperlinked to the handout page containing each item in the TOC – similar to an E-book.

What makes this investment of time and money worth while?
This course has trained over 2,000 professionals in the USA and Middle East since 1979.
The course initially was a 2-week course sponsored by the Division of Safety, National Institutes of Health and the National Cancer Institute until 1983.

What is unique and valuable about this opportunity?
This course reflects my continued commitment to train biosafety officers, clinical laboratorians, researchers, public health professionals, architects, and engineers.
Attendees benefit by learning the origins of and current biosafety knowledge.

My experience as a Research Microbiologist, Author, Biosafety Trainer, and Former Medical School Faculty member includes:
Fifteen years of continuously funded medical school basic and clinical microbiology research at a Philadelphia medical school.
Thirty-five years of professor faculty research/teaching experience at: Johns Hopkins University, University of Maryland Baltimore, and Medical College of Pennsylvania (Drexel University College of Medicine).

Thirty-three years of biosafety/research/management experience as:
Biosafety Division Director at Johns Hopkins Medical Institutions (University & Hospital).
Research Compliance Officer at the University of Maryland Biotechnology Institute.
Research and Development Manager at Becton Dickinson Diagnostic Systems.
Pharma/Biotech/Federal IBC Memberships.

What was the information learned enable the attendee to do better in their job, organization, career?
This course covers all inclusive biosafety references, practices, and templates that can be applied to any biomedical research organization.
The course contains the information needed to pass the certification examination to become an ABSA International Certified Biological Safety Professional,

The Major Course Topics:
Airborne Transmission, including Covid-19 findings.
Biosafety Sources of Information, including the BMBL-6 and WHO-4 Biosafety Manuals.
Laboratory Design & Certification.
Biosafety Cabinet Selection, Installation, Use, Lifespan, and Decommissioning.
Risk Management Principles and Practices.
Infectious Waste Disposal.
Bloodborne Pathogens Regulations and Guidelines.
Microbiological Practices & Techniques.
Recombinant and Synthetic Nucleic Acid Research.
IBC Program Management.
Decontamination & Disinfection Principles and Practices.

Educational Objectives: Upon completion of this course .

Control of Biohazards Newsletter Archive.

Website: https://www.legionella.com/biosafety-training.

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Two Overlooked Biosafety Practices Can Reduce LAIs 31 May 2022, 3:38 pm

Two practices that reduce laboratory acquired infections.

Proper Handwashing Technique.

Wet your hands with clean, running warm water and apply non-antimicrobial, viscous soap in your palms.
[antimicrobial soaps change your normal protective flora and will dry the skin].
[non-viscous soap will not persist during hand rubbing].

Lather your hands by rubbing them together with the soap. Be sure to lather the backs of your hands, between your fingers, and under your nails.

Scrub for at least 20 seconds. Need a timer? Hum the “Happy Birthday” song from beginning to end twice.

Rinse your hands well under clean, running water.

Dry your hands using a clean paper towel.

Turn off the water with the paper towel and discard into trash.

No Hand-To-Face Contact (HFC)

BSL-2 workers recorded 396 touches to the face (mean = 2.6 HFCs/hr).

93 subjects, 67 (72%) touched their face at least once, ranging from 0.2–16.0 HFCs/hr.

Journal of Occupational and Environmental Hygiene. 2014;11(9):625-632.

Pathogen transmission in the laboratory is thought to occur primarily through inhalation of infectious aerosols or by direct contact with mucous membranes on the face. While significant research has focused on controlling inhalation exposures, little has been written about hand contamination and subsequent hand-to-face contact (HFC) transmission.

HFC may present a significant risk to workers in biosafety level-2 (BSL-2) laboratories where there is typically no barrier between the workers’ hands and face. The purpose of this study was to measure the frequency and location of HFC among BSL-2 workers, and to identify psychosocial factors that influence the behavior. Research workers (N = 93) from 21 BSL-2 laboratories consented to participate in the study. Two study personnel measured workers’ HFC behaviors by direct observation during activities related to cell culture maintenance, cell infection, virus harvesting, reagent and media preparation, and tissue processing. Following observations, a survey measuring 11 psychosocial predictors of HFC was administered to participants.

Study personnel recorded 396 touches to the face over the course of the study (mean = 2.6 HFCs/hr). Of the 93 subjects, 67 (72%) touched their face at least once, ranging from 0.2–16.0 HFCs/hr. Among those who touched their face, contact with the nose was most common (44.9%), followed by contact with the forehead (36.9%), cheek/chin (12.5%), mouth (4.0%), and eye (1.7%). HFC rates were significantly different across laboratories F(20, 72) = 1.85, p = 0.03.

Perceived severity of infection predicted lower rates of HFC (p = 0.03). For every one-point increase in the severity scale, workers had 0.41 fewer HFCs/hr (r = −.27, P < 0.05). This study suggests HFC is common among BSL-2 laboratory workers, but largely overlooked as a major route of exposure. Workers’ risk perceptions had a modest impact on their HFC behaviors, but other factors not considered in this study, including social modeling and work intensity, may play a stronger role in predicting the behavior. Mucous membrane protection should be considered as part of the BSL-2 PPE ensemble to prevent HFC.

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Legionella Regulations and Guidelines 23 Mar 2022, 1:04 pm

Management of Legionella in Water Systems.

A Consensus Study Report of The National Academies. Copyrite 2020. National Academies Press. Washington, DC.

Chapter 5. Regulations and Guidelines on Legionella Control in Water Systems:

Lack of Federal Laws and Regulations Pertinent to Legionella.

State and Local Regulations and Other Enforceable Policies.

Guidance Documents.

Regulations and Policies From Other Countries.

Steps Forward for United States Legionella Management:

• Recommendation 1. Expand the CMS Memorandum to Require Monitoring for Legionella in Environmental Water Samples.

• Recommendation 2. Register and Monitor Cooling Towers.

• Recommendation 3. Require Water Management Plans for All Public Buildings.

• Recommendation 4. Require a Temperature of 60°C (140°F) at Hot-Water Heaters and 55°C (131°F) to Distal Points.

• Recommendation 5. Require a Minimum Disinfectant Residual Throughout Public Water Systems and Concomitant Monitoring for Legionella.

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Educational Objectives – Former Workplace Control of Biohazards Course 3 Jan 2022, 6:22 pm

FORMER CONTROL OF BIOHAZARDS IN THE CLINICAL & RESEARCH LABORATORY
Educational Objectives.
Dr. Richard Gilpin RBP CBSP SM(NRCM).

Title: Biosafety Sources.
Objectives: Upon completion of this activity, participants should be able to:
Interpret and apply regulations associated with animal pathogens.
Discuss the difference between the American Association for Laboratory Animal Science and the Association for Assessment and Accreditation of Laboratory Animal Care.
Utilize biosafety web links and publications provided by the ABSA International and the American Society for Microbiology (Biological Safety Principles and Practices).
List biosafety-related publications such as: Hot Zone, Biohazard, The Demon in the Freezer, and Outbreak (Cases in Real-World Microbiology).
Discuss the impact of Public law 107-56 (USA Patriot Act) and the Public Health Security and Bioterrorism Response Act on research.
Discuss the Bureau of Industry and Security Export Control program.
Summarize the CDC National Laboratory Response Network.
Review the BMBL-6 and WHO-4 Laboratory Biosafety Manuals.
Review HHS 42 CFR Parts 72, 73 and 1003 Possession, Use and Transfer of Select Agents and Toxins.
Review the USDA 7 CFR Part 331 and CFR 9 CFR Part 121 Agricultural Bioterrorism Protection Act.
Describe the impact of the Citizenship and Immigration Services regulations on microbiological research.
Plan a Department of Defense Biological Defense Safety Program for your institution.
Identify federal and non-profit associations that provide regulations and guidelines for hospital biosafety such as CDC and Joint Commission.
Interpret and apply OSHA law, standards, and directives as they relate to biohazards.
Demonstrate familiarity with agencies & their relationship with biosafety –
WHO, CDC, CDC-NIOSH, CDC-ATSDR, NIH, OSHA, AAALAC, DOT PHMSA, IATA, ICAO, DOD, EPA, Energy, FBI, USDA, & FDA.
Provide and interpret biosafety resource and reference information from the National Institutes of Health and the Public Health Agency of Canada.
List microbiology and biosafety references such as: Lang Series, Jawetz, Melnick & Adelberg’s Medical Microbiology,
Medical Center Occupational Health and Safety, National Academies Guide for the Care & Use of Laboratory Animals,
& Occupational Health and Safety in the Care and Use of Research Animals.
Employ uniform biological material transfer agreements.
Recommend practices for personnel preparing cytotoxic drugs.
Recommend practices for sorting unfixed cells.
Identify and register research with recombinant or synthetic NA, human tissue, pathogens, select agents and toxins, and carcinogenic, highly toxic and hazardous chemicals.
Develop a research tracking database.
Evaluate laboratory survey field checklists.
Discuss COB Abbreviations.
Discuss Organization Acronyms, CDC Public Health Laboratories Abbreviations, Diskgen Desktop Genetics Glossary,
Glossary of Molecular Biotechnology Terms, Glossary of Commonly Used Terms in Human Subject Protection,
& Glossary of Commonly Used Terms in Gene Therapy & Immunotherapy for Cancer.

Title: Airborne Dissemination of Biohazards.
Objectives: Upon completion of this activity, participants should be able to:
Review the discovery of microbial pathogens and parallel reports of laboratory acquired infection.
Review published laboratory acquired infections survey data.
Become aware of laboratory procedures that produce droplets and how to reduce them.
Identify environmental variables that influence microbial survival.
Plan aerosol experiments to demonstrate sampling methods.

Title: Facility Design.
Objectives: Upon completion of this activity, participants should be able to:
Review the role of secondary barriers for prevention of laboratory acquired infection.
Describe the differences between facilities designed for different levels of containment.
Become familiar with parameters to be audited in a maximum containment facility.
Learn the design specifications of containment facilities.
Discuss the costs involved when renovating or building containment facilities.
Be able to find documents describing the design of biological research facilities.

Title: Biosafety Cabinets.
Objectives: Upon completion of this activity, participants should be able to:
Review the role of primary barriers for prevention of laboratory acquired infection.
Describe how HEPA/ULPA filters trap particles.
Identify the classes and types of biosafety cabinets and their applications.
Review NSF 49 Annex 1 guidelines.
Review the activities of NSF international.
Become familiar with performance tests at NSF and in the field.
Describe when BSCs should be certified.

Title: Risk Management Principles.
Objectives: Upon completion of this activity, participants should be able to:
Describe the types of host/parasite relationships.
Summarize pathogen virulence factors and modes of action.
Discuss Koch’s Postulates.
Classify disease causing organisms.
Perform risk analysis of microbial procedures.
Explain natural host defense mechanisms.
Sketch disease modes of transmission.
Develop, evaluate, and document exposure control procedures for biohazardous agents and materials.
Understand and apply monitoring techniques and equipment to determine effectiveness of exposure control measures and to investigate environmental problems.
Demonstrate knowledge of personal risk factors associated with microbial exposure.
Demonstrate familiarity with routes of exposure, modes of transmission, and other criteria that determine the hazard category of a microorganism.
Assess the risk to the community from various work environments where infectious agents or sensitizing materials may be present.
Understand factors that may affect susceptibility, resistance, or consequences of infection.
Discuss differences between screening and surveillance and the principles of surveillance.
Prepare a medical surveillance program for your institution.
Predict the types of issues encountered if the medical surveillance provider is an outside medical clinic.
List federally mandated surveillance programs and the limitations of early biological effect markers.
Discuss biosafety aspects of COVID-19 disease coronavirus , Zika virus, and Ebola virus.

Title: Bloodborne Pathogens Standard.
Objectives: Upon completion of this activity, participants should be able to:
Review the OSHA 29 CFR 1910.1030 standard and the revised needlestick and other sharps injury regulation.
Interpret frequent OSHA bloodborne pathogen-related citations.
Plan a program for management of bloodborne pathogen exposures.
Assure documentation of worker exposure to biohazardous materials and preparation of an incident report.
Report the modes of transmission and microorganisms involved in occupational exposure to bloodborne pathogens.
Identify post exposure prophylaxis and/or treatment for HIV, HBV and HCV.
Provide recommendations for prevention and control of HCV infection.
Discuss the OSHA 300 reporting regulations.
 
Title: Handling Infectious Waste.
Objectives: Upon completion of this activity, participants should be able to:
Explain the EPA Infectious waste guidelines and the EPA medical waste tracking act.
Review commercial, industrial, medical and education generators of infectious waste.
Plan procedures for infectious waste segregation, transport, packaging and storage.
Summarize current best practices for decontamination of pathological, clinical and research infectious waste.
Propose vendor sources for infectious waste and sharps disposal containers.
Interpret and apply guidelines and state regulations relating to treatment and disposal of infectious and medical waste.
Develop and implement an infectious-medical waste management program.

Title: Biosafety Practices & Techniques.
Objectives: Upon completion of this activity, participants should be able to:
Select and understand use of personal protective equipment.
Select and understand use of respiratory protection equipment.
Develop comprehensive emergency response plan for biohazard areas.
Identify sources of biosafety training videos and programs.
Institute, evaluate, and document biosafety training.
Review architectural and engineering plans and advise on biosafety issues.
Review documented laboratory accidents reported in the news media.
Analyze microbiological practices involving access control, hygienic practices, gloves, eye protection, nose and mouth protection, gowns,
head and foot covers, standard precautions, control of aerosols, housekeeping practices, emergency eyewash/shower systems.
Discuss start up practices before using a biosafety cabinet.
Develop safety practices for sorting unfixed cells.
Recommend emergency procedures for spills inside and outside containment equipment.
Organize an laboratory emergency response plan based on the National Safety Council Emergency Response Plan.
List laboratory-related regulations.
Discuss items often overlooked in the laboratory.
Evaluate relevant codes and standards applicable to research laboratories.

Title: Recombinant or Synthetic NA Guidelines and IBC Programs.
Objectives: Upon completion of this activity, participants should be able to:
Discuss the current NIH Guidelines.
Evaluate the risks associated with recombinant or synthetic NA technology.
Interpret the definitions of recombinant or synthetic NA and apply the NIH Guidelines for research involving recombinant or synthetic NA molecules.
Discuss the roles of the Office of Science Policy, the National Science Advisory Board for Biosecurity,
Institutional Biosafety Committees, Biosafety Officers, and Principal Investigators.
Review the connections between IBCs, Institutional Review Boards, and Institutional Animal Care and Use Committees.
Describe the NIH Guideline reference categories.
Examine the FDA Center for Biologics Evaluation and Research and the Environmental Protection Agency role in recombinant or synthetic NA research.
List molecular biology education and training materials.
Interpret and apply guidelines that classify biohazardous agents according to risk.
Discuss genomic and plasmid isolation and purification methods and the differences between Northern, Southern and Western blots.
Examine prokaryotic cloning vehicles and eukaryotic cell transformation methods.
Illustrate gene transfer vehicles used in gene transfer clinical trials.
Summarize major vectors used in recombinant or synthetic NA research.
List non-viral based gene transfer systems.
Review ex-vivo and in-vivo somatic cell transfer.
Interpret large DNA fragment cloning libraries including YACs, BACs and PACs.
Review documents needed to implement and manage an IBC program.
Review molecular biotechnology terms.

Title: Decontamination & Disinfection.
Objectives: Upon completion of this activity, participants should be able to:
Describe the differences between sterilization, decontamination, and disinfection and the applicability and means of monitoring each of these processes.
Summarize the population dynamics of microbial inactivation and the factors that affect microbial destruction or inactivation.
List the properties of an ideal disinfectant.
Review the gases used for chemical disinfection or sterilization (vapor phase hydrogen peroxide, chlorine dioxide gas, formaldehyde gas,
hydrogen peroxide vapor plasma, ozone, low temperature steam formaldehyde and peracetic acid vapor.
Review the liquids used for chemical disinfection or sterilization (halogens, quaternary ammonium salts, phenolics, aldehydes, alcohols,
heavy metals, iodophors, amphoteric surfactants, organic sulfur compounds, peracetic acid, formic acid and sodium hydroxide.
Evaluate activity levels of germicides for disinfection of surfaces.
Recognize the heat processes for physical decontamination and sterilization (dry heat and moist heat).
Discuss the differences between chemical indicators and biological sterilization indicators.
Propose an autoclave quality assurance program for decontamination of waste.
Demonstrate knowledge of use, applicability, and potential hazards (explosive, flammable, corrosive, carcinogenic, and irritating)
associated with various disinfectants and sterilants.
Discuss the use chemicals, steam, dry heat, irradiation, filtration, ultraviolet (UV) sources, gases, or other agents to kill or inactivate microorganisms.
Predict the shortcomings of germicidal ultraviolet light decontamination of surfaces.
Apply equipment and chemical methods for decontamination of rooms.
Review filtration processes for physical sterilization of liquids.
Summarize the procedures and processes for inactivation of Bacillus spp. Spores.
Describe the procedures for inactivation and safety containment of biological toxins.

Title: Biological Packaging & Shipping.
Objectives: Upon completion of this activity, participants should be able to:
Review the definitions and classes of dangerous goods (hazardous materials).
Discuss US Transportation Security Administration and Public Laws.
List international and US regulations applicable to shipment of dangerous goods.
Review the United Nations regulations promulgated by the International Civil Aviation Organization (ICAO) basis of the International Air Transport Association (IATA) regulations.
Contrast the training requirement differences of the US Department of Transportation (DOT) and IATA.
Locate DOT shipping information on the internet.
Describe the dangerous goods carry on or checked baggage rules.
Discuss Dangerous Goods Excepted Quantities Declaration for carry on or checked baggage.
Review in detail Class 6, Division 6.1 Toxic Substances and Class 6, Division 6.2 Infectious Substances.
Review the Category A table of infectious agents.
Identify the classification of biological products, genetically modified microorganisms and organisms and biological substances exempted from shipping regulations.
Utilize the Infectious Substance Category A Packing Instruction 620 to ship infectious substances.
Apply the supplied template to construct a Dangerous Goods Declaration for shipment of Infectious Substance Category A on dry ice.
Utilize the Category B Biological Substance Category B Packing Instruction 650 to ship biological substances.
Utilize the dry ice packing instruction 954 to ship dry ice.
Utilize the liquid nitrogen packaging instruction 202 to ship materials in liquid nitrogen and the exemption for dry shippers.
Apply the supplied template to construct an Air Waybill to ship non-dangerous goods on dry ice.
Discuss regulations for shipment of select agents and toxins.
Review CDC import permits and APHIS import and transport permits.
Use the Commerce Department list to determine whether an export permit is required for shipments outside the US.
List Division 6.2 container vendors and shipping companies.
Review DOT PHMSA and US Postal Service shipping regulations and their applicability when shipping by air.
Propose guidelines for transporting clinical and biological specimens from outside clinics, labs or homes to a research or clinical laboratory.
Evaluate the containment devices for transport of infected live animals.

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Typical Sources of Community-Acquired Legionnaires’ Disease 10 Nov 2021, 12:15 am

1) In my opinion, sporadic cases of Legionnaires’ disease [LD] probably come from exposure to airborne droplets containing Legionella pneumophila from cooling tower drift during warm days when the relative humidity is equal to or greater than 80% – particularly during periods of heavy rainfall.

2) If we were going to design a piece of mechanical equipment that would perfectly simulate the aerobic, natural freshwater environment for Legionella growth, cooling towers would be the result.

https://www.coolingtowerproducts.com/blog/how-cooling-towers-work-diagram-pictures-2015.htm .

3) Legionella bacteria are aquatic freshwater, obligate aerobes that live at the air-water interface in freshwater lakes, streams, ponds, and in water-containing mechanical equipment open to the environment, such as cooling towers, evaporative condensers, and fountains.

4) Legionella bacteria die in stagnent water plumbing lines because of low oxygen levels. Legionella bacteria can only survive these low oxygen conditions by colonizing and living within aquatic amoeba and other related protozoan microorganisms. Legionella bacteria are facultative intracellular parasites. That allows them to live inside some cells [similar to the way that Coxiella bacteria grow inside cells and cause the disease Q-Fever].

5) The reason that Legionella bacteria can multiply in human lung air sac alveolar macrophages is because they provide the growth conditions that approximate the natural freshwater amoeba hosts for Legionella [Ines G. Goncalves et al. September 01, 2021. Microbe of the Month. Vol.29. Issue 9. Pages 860-861].

6) When Legionella grow inside lung air sac alveolar macrophages, they cause tissue damage. The body mounts a response to Legionella presence with an inflammatory, thrombotic, and fibrinolytic response resulting in pneumonia with the formation of large quantities of fluid in the lungs, similar to drowning [2001, New England Journal of Medicine, Vol. 344:700].

7) The U.S. Department of Commerce, National Atmospheric Administration, National Environmental Satellite Data and Information Service provides local climatological data monthly and daily summaries for most areas of the country. National Centers for Environmental Information data provided for a particular city or area will show when warm temperatures, high humidity, and heavy rainfall occur. This information can be used to correlate with community-acquired Legionnaires’ disease cases in that area. We used this information to correlate weather and Legionella counts during an investigation of a cooling tower that was published in 1985.

8) There are more community-acquired Legionnaires’ disease cases during warm, humid, heavy rainy weather: “LD is more likely to occur in warm (60°–80°F) and very humid (>80.0%) months. For example, the odds of LD being diagnosed in a pneumonia patient during a month when the rainfall is <18 mm and the temperature is 60°–80°F was 3.1 times higher when the relative humidity was >80.0% than when it was <50.0%. When rainfall amounts were greater, the risk also increased; however, regardless of rainfall, warm and humid weather was a major risk factor. Also, we found a dose-response relationship between relative humidity and the odds of an LD diagnosis during periods of warm weather. In contrast, hot, cool, or dry weather patterns produce no meaningful increase in LD.” [“Weather-Dependent Risk for Legionnaires’ Disease, United States.” Jacob E. Simmering, et al., Emerging Infectious Diseases, November 2017, Vol. 23, Number 11, Pages 1843–1851].

9) Cooling towers transmit Legionella greater than 1-mile. Cooling towers and evaporative condensers produce large volumes of droplet aerosols. Cooling towers have been found to be the sources of community outbreaks in a number of published investigations. For example, “Community Outbreak of Legionnaires’ Disease: An Investigation Confirming the Potential for Cooling Towers to Transmit Legionella Species.” David W. Keller, et al. Clinical Infectious Diseases, 1996, Vol. 22, Pages 257-61 © 1996 by The University of Chicago.

10) Google Scholar search words |cooling tower legionella transmission distances| produces several peer-reviewed papers documenting large distance transmission. Such as, “Community-acquired Legionnaires’ disease associated with a cooling tower: Evidence for longer-distance transport of Legionella pneumophila.” David G. Addiss et al. September 1989, American Journal of Epidemiology, Vol. 130, Issue 3, Pages 557–568.

11) Why are today’s Legionella testing methods often unable to detect Legionella in cooling tower water? Today’s Legionella testing methods are based on research with potable water supplies. We need environmental microbiology researchers, not engineers, to develop useful Legionella tests of cooling tower water that contains heavy metals, debris, etc.

12) Forty-five-years after the 1976 Philadelphia cooling tower outbreak, we still do not have adequate testing methods to locate sources of airborne droplets containing Legionella bacteria emerging from water-containing mechanical equipment such as cooling towers.

13) The current agar culture and genetic marker qPCR testing methods usually find Legionella in potable water samples, but these methods become inadequate when testing water samples from water-containing mechanical equipment exposed to the environment. The agar tests often produce false negative Legionella test results because many species of microorganisms in the water will either inhibit the growth of Legionella colonies, or the other microorganisms will overgrow the slower-growing Legionella colonies. The qPCR genetic tests are inadequate because the organic and inorganic debris found in cooling tower samples interferes with PCR gene testing by producing high background noise levels so great that the Legionella genetic markers sometimes cannot be detected.

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Air Exchange Rates for BSL-2 & BSL-3 Microbiology Laboratories 21 Sep 2021, 2:01 pm

What should be the exchange rates for BSL-2 and BSL-3 Clinical & Research Laboratories?

Consensus is 6 to 8 ACH.

What are the number/Cubic Foot of viable bacteria & fungi in BSL-2 & BSL-3 Laboratories?

Typically, the same as outside air numbers, except when BSL- 3 lab supply air is HEPA filtered to Class 100,000 [100 CFU per cubic meter].

Most of the below information was abstracted from the Control of Biohazards Course Laboratory Design Lecture handout.

Richard W Gilpin PhD RBP CBSP SM(NRCM).
Director – Control of Biohazards Course.
https://www.legionella.com/biosafety-training/.
Email: gilpin@legionella.com.

NIH Design Manual.

https://www.orf.od.nih.gov/TechnicalResources/Pages/DesignRequirementsManual201 6.aspx.

B.1 Space Ventilation Rates in BSL3 Laboratories: BLS3 laboratories shall be provided with a minimum of 6 air changes per hour.
This minimum air flow shall be maintained at all times, including unoccupied periods.

Certek Modular BSL-3 Facility.

All levels of biocontainment, animal and agricultural containment. http://www.certekinc.com/products/custom-built-modular-laboratories/.

Most BSL-3 Labs do not have HEPA-filtered supply air.

Certek BSL-3 laboratory is up to International Standard Organization (ISO) Class 8. HEPA supply & exhaust air.

ISO Class 8 Cleanroom Information.

Information on ISO 14644-1:2015 class 8 Cleanroom Classification.
Federal Standard 209E equivalent: Class 100,000.

EU GMP Grade equivalent: D.

Air changes per hour required: 5-48.

Typically measured micron sizes: 5.0µ and 0.5µ.

Microbiological Active Air Action Levels: 100 cfu per cubic meter Microbiological Settle Plates Action Levels: 50 cfu (90mm plate, 4 hours).

It is understood that these are recommendations only and you have the discretion to assign levels based on your manufacturing process and method of analysis.

National Institutes of Health. Biosafety Level 3 Laboratory Certification Requirements.

By Deborah E. Wilson, DrPH, CBSP & Farhad Memarzadeh, Ph.D., P.E. July 2006.

11. Verification of air change rates (ACR) in containment spaces.

In no case should the ACR be less than 6/hr for labs and 10/hr for animal facilities.

JHU BSL-3 Lab Gilpin checklist negative pressure. Air Pressure Differentials.

Anteroom shall be at 100 cfm negative with respect to an adjoining space.
Containment laboratory shall be 100 cfm negative with respect to the anteroom.
Usually 6-8 ACH, single pass, constant volume [no variable air volume] air in the 1990’s.

Designing a Modern Microbiological / Biomedical Laboratory.

Jonathan Y Richmond Editor. 1997 American Public Health Association, Washington DC ISBN 0-87553-231-4.

Chapter 8. Designing Laboratory Ventilation. Gregory F DeLuga.

Page 183: “There is no way of reliably knowing what specific chemical or airborne substances will be present and at what concentrations in most laboratory rooms. Furthermore, laboratories can be subjected to unpredictable combinations of airborne agents, thus making the situation still more complex and indeterminate. For these reasons, no scientifically based process exists to determine the appropriate ventilation rate necessary for a given laboratory room.”

Page 186: Table 1 – Minimum air changes per hour (ACH).

ASHRAE HVAC Applications 1995 & ANSI/ASHRAE Standard 62-19895.

Biochemistry 6 to 10.
Animal     10 to 15.
Autopsy           12.

Air Change Rates

Jon Crane formerly at CUH2A ABSA biosafety forum 03Nov07

https://journals.sagepub.com/doi/pdf/10.1177/153567600701200302

“I wanted to further explain my comment that “Studies over the past 25 years have shown that air change rates are not effective at reducing biological contamination in laboratories” (Jon Crane, Applied Biosafety, 12:3, 143).

First I want to emphasize as I stated in the article that “the most common words in containment facility design are “it depends.” In other words, a single answer rarely covers all the issues for all containment facilities. Be sure to examine the applicability of the information provided below for your specific project needs before you implement them.” I believe that every containment situation should be evaluated independently as to the specific needs of the facility. The conclusions in the following discussion of air change rates might not apply to every circumstance. For example, the air change rate is important if you are trying to:

1) Create a classified clean room environment. In these cases, very high air change rates, supply filtration and laminar flow are combined to get down to very low overall particle counts. There are extraordinarily interesting issues that occur in design if you are trying to combine an enhanced BSL-3 facility with a class 100 clean environment. It would take a separate paper to describe the issues that must be resolved in such a case. The fact that a biosafety cabinet combines clean and containment in a micro-environment makes all of our lives simpler. (By the way, calculate the air change rates in your biosafety cabinets and imaging trying to use the same rates in your facility. It may surprise you.).

2) Reduce odor and dander in animal rooms with open caged or loose housed animals to provide an appropriate environment. Air change rates do provide value, however, studies at Penn State University that have been published indicate that even then at relatively low levels air change rates may begin to lose their effectiveness “…in this example, the room initially is contaminated with 100 cfu/m3 and then purged with outside air, which is assumed to be uncontaminated. Results of these calculations show that at 1 ACH, the room can be purged of almost 95% of airborne contaminants in 4 h.

This analysis indicates that doubling or quadrupling the ACH has a great influence on how fast the room can be cleansed but increasing the rate beyond 10 to 12 ACH offers little additional benefit. Obviously, there is some acceptable level of performance above which no gains are likely to be cost-effective.

That is, the cost of moving air for purging contaminants may become prohibitive if the air change rate is too high. To put this into perspective, an ACH of 6 to 12 might be a reasonable goal for any animal laboratory or even a hospital operating room, but any increase above these levels may have limited value. This analysis assumes, as stated previously, that the air is completely mixed. If a facility has poor air-mixing, then there might be benefits from even higher ACH levels. One study on rat rooms found that 172 ACH was necessary to control rat allergens, but such high airflow levels could have prohibitive costs” (Engineering Control of Airborne Disease Transmission in Animal Laboratories, Kowalski, Banfleth and Carey, Contemporary Topics, AALAS, 2002). Keep in mind also that containment caging systems greatly reduce the need for overall room ventilation.

3) Reduce chemical exposure below a set value if chemicals are released in an open environment.

4) Reduce aerosol transmission in patient rooms, waiting rooms, etc.

Conversely, if you have a BSL-4 suit laboratory with no animals or animals in individually ventilated cages, the need for ventilation of the space itself might be minimal as both the personnel and animals would be taken care of with micro-environments (Suits and cages respectively).

If you have a containment facility that has these or other special needs you can look at 1) the aerosol load from both normal operations and the maximum credible event, 2) the safety and operational requirements that would drive the overall reduction and the time for reduction of the aerosols and 3) the effectiveness of the ventilation system design. With those parameters, you can precisely define the ideal air change rates for aerosol control of the design conditions; however, as a practical matter, most facilities will operate well using conventional ventilation system design practices. In addition, rooms are seldom static with perfect mixing. Convection currents, doors opening and closing, furniture, equipment, people movement and animal movement will disrupt the ideal conditions. Containment facilities tend to see a constant change in all these parameters. Remember that heat loads and ventilation equipment requirements are also a factor in dictating air change rates in a containment facility.

I have always tried to look at issues related to the design of containment facilities as to how they impact the day-to-day operation of a containment facility in a practical way. What benefit do you get? What price do you have to pay? In paying the price, does it keep you from getting other features that might provide a higher benefit to safety or operations? To understand the cost versus the benefits you have to dig into the details. In containment facilities, there would be two types of source for aerosol contamination: 1) a constant emission from a process or infected animals or 2) a sudden burst emission from a process or accidental event. Air change rates have a different impact on each of these states.

For a basic containment laboratory with aerosols contained in biosafety cabinets or other primary containment systems the constant emission source is not an issue as the aerosol would be contained within the primary containment device. The concern would therefore be with the sudden release from an accident occurring outside primary containment. (Or from an incident inside primary containment that has enough force to escape the primary containment system.) For these events studies from Penn State and elsewhere have shown that the initial concentration is reduced relatively rapidly with effective ventilation; however, with conventional laboratory systems it would not be rapid enough to prevent exposure to personnel in the space and the mixing is not so absolute to completely remove the aerosol for a significantly longer time period.

An example:

Assuming a ventilation system with good mixing, if you had a spill in a room with six air changes or twenty air changes per hour you would have the higher level (70-100%) of the initial aerosol concentration in the room for the time period it would normally take for the users to safely evacuate the space. In any event, the air change rate would have minimal impact on the initial exposure.

Also, as a practical matter, there is little difference between six air changes and thirty air changes in the length of time it takes to purge the room to a low level of remaining aerosol, In both cases you get below 5% in less than 45 minutes;

If you have the appropriate containment laboratory, there is not a difference in containment risk if you get to 5% concentration in 20 minutes or a 5% concentration in 45 minutes as the laboratory will appropriately handle the aerosols either by filtration or dilution. If it is necessary to rush into the room quickly after the incident, as in the case of a medical emergency being the root cause of a release outside of primary containment, prudent practice would have the response team wearing respiratory protection. In any case, air change rates would not significantly change the aerosol load at this point. If you can wait to respond, the difference between waiting 20 minutes or 45 minutes would also not likely be significant. Again, however, each facility should address the value of this length of time to their operations.

Based on the above, I don’t see significant benefits for most facilities in increased air changes. I do see significant additional costs for higher air change rates.

For a 5,000 SF laboratory, the difference in cost for heating and cooling as you move from six to twenty air changes would be in the range of $40,000 – $50,000 per year. If the facility is HEPA filtered, there would be an additional large cost for the fan energy to pull the difference in quantity of air through the filters. As air change rates affect filter sizes, duct sizes, air handling unit sizes, exhaust fan sizes, exhaust valve sizes, etc., the first costs for installing the larger system would be proportionally higher as well. These to me become significant enough costs to carefully examine if the minor benefits you might get from higher air change rates would be worth the initial and ongoing costs.

Again, it is important to point out that in some cases the benefit may be worth the cost of the higher air changes. For any specific facility, I am not advocating one answer or the other. I am advocating that you analyze the cost versus benefit for your situation. In my opinion that is the only way you will get the best answer to meet your needs.

As I mentioned in the ABSA Journal editorial, I have run across papers over the years that support the argument that in a containment laboratory, there is little real benefit to safety from increased air changes. One of the older but better papers was by Emmet Barkley in which he examined the impact of various safety measures and engineering controls on the reports of laboratory acquired infections at that time. He stated that “It is difficult to assess the value of air exchange rates as a hazard control factor. It is my general feeling that no ventilation rate associated with conventional mixing and air distribution within a laboratory would substantially reduce the inhalation dose that an individual might be exposed to if infectious materials were accidentally released into this environment. Protection from exposure to burst sources can only be practically achieved using biosafety cabinets. To achieve a similar level of protection through room ventilation practices would require high-velocity laminar flow facilities in which the investigator would always be upstream of the materials being handled. This condition is obviously impractical and terribly expensive.

Conventional ventilation rates (i.e., 6 to 15 air changes per hour) are virtually ineffective in reducing airborne contamination caused by a continuous release of particles. I have, therefore, guardedly concluded that ventilation rate has little relevance as a hazard control factor”.

Everything I have seen or read in the 25 years that I have been involved in the design of containment facilities would lead me to believe that Emmet made a wise assessment of the issue of air change rates related to most containment facilities.

Lastly also remember that air change rates themselves do not create effective ventilation of a space. You can have a high air change rate with poor system design and not get any benefit.”

New Approaches to Pressure Stability in BSL-3 Containment Labs: Minimized Turbulence, Mix of Control Strategies Keep Pressure Relationships on Track.

Published: 12-20-2017.

https://www.tradelineinc.com/reports/2017-12/new-approaches-pressure-stability- containment-labs.

The golden rule of containment is to always maintain the relationship between exhaust and supply.

Typical room pressurization is guided by a rule of thumb: It takes an offset airflow of 100 to 150 CFM per door to attain the target pressure. “This rule assumes the space is basically airtight with leakage only around the door frame and the door undercut.

Studied four existing BSL-3 labs, each with multiple rooms of a consistent geometry (similar layout and door size, same controls). They collected 874 data points related to flow and differential pressure. The analysis of the data ultimately confirmed the relationship between differential pressure and airflow in the facilities as a function of the geometry of the transfer openings.

With its connections to all spaces, the corridor has a pivotal role to play in the containment strategy for the entire suite. Often regarded as least important, because it does not house primary research, the corridor (or similar anchor space) is actually the hub. “It’s inherently a central anchor from the control standpoint.”It follows that equipping the corridor with the higher performance of a direct pressure control system would enhance containment capabilities of the suite as a whole.

“Under direct control, if something happens in a lab, the corridor acts as a workhorse, absorbing, minimizing, or mitigating pressure fluctuations. The other rooms aren’t affected, and the problem doesn’t propagate.”

A further potential enhancement is a primary-secondary valve configuration for corridor supply air. The larger secondary valve provides the requisite air volume, while the smaller primary valve enables fine-tuning for space pressure control.

With the corridor under direct control, the other rooms in the suite can operate effectively under progressive offset control. Clements and Stanford point out that the mix of control types should be systematic throughout the facility, with all procedure rooms operating one way, and all corridors another.

Air change rates recommended in various standards and selected projects

Standard/Guideline. Recommended Air-Change Rate.

ANSI/AIHA Z9.5-2003. The specific room ventilation rate shall be established or agreed upon by the owner or his/her designee.

NFPA-45-2004. Minimum 4 ACH unoccupied. occupied “typically greater than 8 ACH.

ACGIH Ind. Vent 24th Ed. 2001. The required ventilation depends on the generation rate and toxicity of the contaminant-not on the size of the room in which it occurs.

ASHRAE Lab Guide-2001. 4-12 ACH.

OSHA 29 CFR Part 1910-1450. 4-12 ACH.

Project. Specified Air-Change Rate.

UC Santa Cruz Bio-Med Building. 6 ACH occupied, 4 ACH unoccupied.

UC Davis Tahoe Center. 6 ACH occupied, 4 ACH unoccupied in low-risk labs.

UC Berkeley Li-Kashing Building. 6 ACH.

Energy Efficient Laboratory Design: A Novel Approach to Improve Indoor Air Quality and Thermal Comfort.

Farhad Memarzadeh-1, Andy Manning-2, and Zheng Jiang-2.

1-National Institutes of Health, Bethesda, Maryland and 2-Flomerics, Inc., Marlborough, Massachusetts. Applied Biosafety Vol. 12, No. 3, 2007.

https://journals.sagepub.com/doi/pdf/10.1177/153567600701200303.

The results of this study show that chilled beams improve thermal comfort and can be operated at reduced Air Changes per Hour (ACH) while maintaining a comfortable environment in occupied zones expressed as the Predicted Percentage Dissatisfied (PPD).

To obtain a similar level of thermal comfort, a higher ACH is required in a ceiling diffuser system with cooling panels and bench exhausts.

The following conclusions can be drawn from this study:

1.   Chilled beams improve thermal comfort and can be operated at as low as 4 ACH (without a fume hood in the laboratory) while maintaining very satisfactory average PPD (around 10%) in the occupied zones.

To obtain a similar level of thermal comfort, 6 ACH is required for ceiling diffuser system with two sets of cooling panels and bench exhausts.

2.  The presence of an operational fume hood slightly improves the thermal comfort in the room.

3.  The average concentration in the occupied zone caused by the bench top spills increases when the primary flow rate decreases but is not very sensitive to the change of primary air flow rate. The chilled beams improve the removal effectiveness of gases and airborne particles by generating a better mixed condition in the room than ceiling diffusers.

4.  The chilled beams in the cases studied are seen to have an insignificant effect on the hood containment.

5.  Using chilled beams with a fume hood, satisfactory thermal comfort and air quality can be achieved at 6 ACH (100% Outside Air) in comparison with an all-air ceiling diffuser ventilation system at 13 ACH (70% Outside Air), which indicates a 22.5% saving in annual energy costs for cooling and ventilating a typical lab in the Washington, DC area.

It should be noted that the use of chilled beams is not intended to be applicable to all types of laboratories and should not override the contaminant controls that are appropriate for this type of laboratory, particularly with respect to the use of appropriate biosafety cabinets (BSCs) and/or fume hoods, and the handling of hazardous materials on the workbenches.

Finally, the usefulness of the chilled beam system may not be beneficial from a cost standpoint in scenarios where the room flow rate is already low, and energy costs are relative to other occupied spaces.

Study on contaminant distribution in a mobile BSL-4 laboratory based on multi-region directional airflow.

Yan Wang et al., Accepted: 3 September 2021. Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature 2021.
https://link.springer.com/content/pdf/10.1007/s11356-021-16394-w.pdf

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