Acumen Series: White Papers

The following is our collection of Acumen issues:

Volume 11 No. 1

Hypoxia Workstation with HEPA-Filtration Option Demonstrates Enhanced Containment to Protect User

Read Abstract

• Hypoxia workstations are utilized by researchers who require stable and accurate low oxygen environments for their research. Oxygen, carbon dioxide, temperature and humidity are precisely controlled within the work area of the workstation to simulate an in vivo environment and create optimal conditions for the experiment.
• Hypoxia workstations are closed glove boxes. They allow air from inside the workstation (which is under positive pressure relative to the room) to be released directly to the laboratory by design, and do not typically provide protection to personnel from potential contaminates in the exhausted air. If biological agents may be aerosolized within the workstation, it is important that biosafety officers have containment performance data to perform a complete risk assessment.
• An enhanced containment option was developed for the Ruskinn Invivo2 hypoxia workstation. This option was microbiologically tested at The Baker Company in order to quantify the release of a microbiological aerosol from the workstation to the laboratory environment. This paper describes the test procedure and presents results that can then be used to determine the risk to the laboratory researcher associated with various types of laboratory work.

Volume 3 No. 3

New Animal Transfer Station Offers Improved Containment and Allergen Control

Read Abstract

• When using animals in research, protecting the animal from both the lab environment and cage-to-cage cross-contamination are a researcher’s highest priorities. Today, increased awareness of the potential health hazards presented to laboratory workers by animal allergens has led to an increase in the importance of personnel protection as well.
• Typically when personnel, product, and environmental protection are required, a Class II biosafety cabinet is used. However, easy access to the work area and maneuverability are key benefits for equipment used for animal transfer and cage-changing procedures, so biosafety cabinets can present some productivity challenges. Recognizing this need, The Baker Company (Baker) developed the AniGARD® e3, a new animal transfer station clean bench designed to enhance containment and protection while increasing productivity.
• The AniGARD® e3 was subjected to rigorous testing in the Baker laboratory to determine air cleanliness, protection of the product (animal) from contamination from the environment, potential allergen exposure to the user, as well as cross-contamination between cages. Because there is no established industry standard or test for quantifying the level of protection and containment in an animal transfer station, Baker adapted existing standards. Armed with this data, a laboratory manager or researcher can be assured that the AniGARD e3® will fit their needs as determined by a risk analysis.
• The unit achieved an ISO Class 4 air quality rating for air cleanliness. Product (animal) protection provided by the AniGARD® e3 was found to be equivalent to a biosafety cabinet, and personnel protection (allergen control) approached the level of a biosafety cabinet. Finally, negligible cage-to-cage cross contamination occurred within the work area of the AniGARD® e3.
• This paper describes the test methods employed and the pursuant results.

Volume 10 No. 3

Biological Safety Canopy Exhaust Connection Saves Energy and Improves Overall Safety Performance

Read Abstract

• With environmental resources becoming more and more limited and energy costs on the rise, reducing energy consumption is an important consideration for every laboratory. It is especially important in light of an analysis published by the US Environmental Protection Agency concluded that laboratories consume five to 10 times more energy per square foot than typical office buildings.
• As one of the most frequently used devices in the laboratory, biological safety cabinets (BSCs) provide the primary source of containment for microbiological research. BSCs are critical for the protection of personnel from exposure to airborne biohazards and other potentially harmful particulates within the cabinet. BSCs also provide product protection from contaminants outside the cabinet environment through the use of a HEPA-filtered airflow that is contained within the BSC. This vertical unidirectional downflow air combined with suction below the intake grille prevents outside airborne contaminants from entering the cabinet’s workspace.
• Class II Type A2 BSCs can either exhaust HEPA-filtered air back into the laboratory or outside through a canopy exhaust connection (CEC). When vented to the building exhaust system, a BSC becomes the first piece of system ductwork, and the facility's HVAC design must accommodate duct static pressure and exhaust flow values. Exhausted air must be replaced by a laboratory’s air supply system and typically needs to be conditioned (either heated or cooled). BSCs are often operated continuously, so conditioned air can add considerable operating costs to a laboratory over time.
• The Baker Company (Baker) has developed a patent-pending CEC, FlexAIR™ that can provide significant savings for laboratories by reducing the amount of exhaust required to operate a BSC. The FlexAIR also allows a cabinet to maintain product and personnel protection standards over a wide range of exhaust system fluctuations, even if a building’s exhaust system fails. The following paper demonstrates how the FlexAIR reduces both total exhaust flow and the amount of conditioned air required, while providing a higher level of protection than traditional canopy connections.

Volume 10 No. 2

Innovative Technologies Result in a More Sustainable and Energy-Efficient Total Exhaust Biological Safety Cabinet

Read Abstract

• Biological safety cabinets (BSCs) provide the primary source of containment for microbiological research. Laboratories that need containment and removal of vapors, mists and particulates will often choose a Class II, Type B2 total exhaust BSC (Type B2). Because this type of BSC must be totally exhausted to the outside through a facility’s HVAC system, it requires a great deal of energy to operate and can add significantly to a laboratory or facility’s operating costs.
• According to an analysis published by the U.S. Environmental Protection Agency, laboratories consume 5 to 10 times more energy per square foot than typical office buildings. Access to more energy-efficient equipment, without any sacrifice in safety and performance, will allow labs to decrease not only energy consumption and operating costs, but also their environmental impact. The BioChemGARD e3 total exhaust BSC from The Baker Company (Baker) is engineered to help achieve this.
• With the BioChemGARD e3, a reduction in exhaust airflow and resistance cuts the electrical power, noise and static pressure requirements for the facility and reduces the volume of conditioned air exhausted from the laboratory. The nominal size 4-foot model operates at only 664 CFM and uses new, three-phase Variable Frequency Drive (VFD) motor technology to help deliver a reduction of up to 86% in electrical power when compared to traditional Type B2 total exhaust cabinets. This combination contributes to an overall reduction in the energy/power consumption requirements for most facility exhaust systems of up to 23%, providing a potential for annual operational cost savings of up to 49% over traditional Type B2 total exhaust cabinets listed with NSF International. Performance and productivity remain high, while protection for both the product and personnel exceed NSF International Standards #49.

Volume 10 No. 1

Energy Efficient Biological Safety Cabinet Reduces Energy Costs While Ensuring Safety

Read Abstract

• As the primary containment devices within laboratories, biological safety cabinets (BSCs) are critical to protect personnel, product and environment from exposure to biohazards and cross-contamination during routine daily procedures. Because of this vital role, the biological safety cabinet is one of the most essential and highly used pieces of equipment within a laboratory.
• Biological safety cabinets have been designed to run continuously to maintain aseptic conditions in the workspace. Additionally, BSCs are often operated continuously to help control dust and other airborne particulates.
• With current energy prices reaching all-time highs, reducing energy costs is a paramount concern of every laboratory. An analysis published by the U.S. Environmental Protection Agency concluded that laboratories consume five to 10 times more energy per square foot than typical office buildings. The need for energy-efficient equipment has never been more acute.
• The Baker Company’s new SterilGARD high-efficiency biological safety cabinets offer a significant reduction in energy usage while maintaining a rigorous standard of safety and protection. Recent studies have shown that the reduced airflow mode of operation for the cabinets results in a 50–75% lower operating cost compared to previous designs.

Volume 9 No. 1

The Baker Compounding Isolators and USP Requirements Pharmacy Barrier Isolators

Read Abstract

• The United States Pharmacopeia (USP) has recently released an In-Process Revision to Chapter - Pharmaceutical Compounding - Steril Preparations.1. The Baker Company has conducted a study to evaluate its pharmacy isolators using the criteria presented in this In-Process Revision. The results in this paper demonstrate that the SterilSHIELD (compounding aseptic isolator - CAI) and the ChemoSHIELD (compounding aseptic containment isolator - CACI) meet the performance criteria required by the In-Process Revision to USP Chapter when located in an environment worse than ISO Class 7. ISO 5 conditions are maintained when the isolators are challenged with background conditions worse than ISO Class 9. Additionally, these requirements are met without the use of cleanroom garb

Volume 8 No. 1

Terminology Changes in the 2002 Revision of NSF 49 NSF/ANSI Standard # 49 – 2002 Class II Biological Safety Cabinets Types

Introduction

• For more than 20 years there has been confusion concerning Class II biological safety cabinet (BSC) terminology. This has led to problems in understanding just what the types of Class II BSCs are, and how they should be installed and used. The changes in the NSF/ANSI Standard 49 - 2002 are intended to resolve many of these issues. A good way to grasp all of this is to become familiar with the evolution of Class II BSC terminology. Achieving this should enable us to properly interpret the relevant literature which contains a myriad of terms that have been applied to Class II BSCs. Additionally, it will make it possible for us to understand each other when we discuss BSCs.

Volume 6 No. 1

Ergonomic Considerations In The Development of A Class II, Type A/B3 Biological Safety Cabinet

Introduction

• The laboratory workplace is changing. More attention is being given to laboratory personnel, their work environment and ergonomics, the science of fitting the workplace to the worker. The Baker Company has developed the SterilGARD^® III Advance° biological safety cabinet in response to these changes. This cabinet, used in laboratory investigation and protocols involving agents of low and moderate risk, includes a number of design features that improve worker productivity and comfort while being used during repetitive tasks.

   

• A Baker Company design team was charged with researching ergonomics issues associated with biological safety cabinets and making recommendations as to a new cabinet design. The team considered cabinet shape, worker position, lighting, containment and a number of other issues in composing design criteria. What resulted is the industry's first Class II, Type A/B3 biological safety cabinet that recognizes the principles of ergonomics and worker comfort and is built with Baker's reputation for performance.

Volume 5 No. 1

Continuous-Flow Bypass For Improved Fume Hood Performance

Read Abstract

• The "roll" of air which forms inside a fume hood immediately behind the sash can be a reservoir for contaminants. Air recirculates at that location rather than exiting the hood immediately. So contaminant concentrations may be higher in the "roll' than at other point inside the hood.
• The matter is of some concern, because the roll is close to the breathing zone of the scientist performing the work. The current project investigated a means of reducing the concentration of contaminants directly behind the sash. If this concentration is reduced, any leakage would be less hazardous to workers in the lab.
• The method, called the continuous-flow bypass, introduces a constant stream of air into the hood above the sash, delivering dilution air directly to the roll. The method reduced contaminant concentration by 50 to 90%, which significantly reduces the hazard potential of any leakage.

Volume 4 No. 1

The Bio-Analog Test For Field Validation of a Biosafety Cabinet Performance

Read Abstract

• The "Bio-Analog Test" is a test protocol which can be used in the field to quantify actual containment and prduct protection performance of a biosafety cabinet. Results obtained through this method have been correlated with the microbiological test. The test is relatively fast, and does not require the use of microorganisms, which could contaminate ongoing research in the laboratory. Also, the test can used to quantify the "protection factor" provided by the cabinet in the as-used condition, a function which at present is impractical to determine through any other method.

Volume 3 No. 1

Risks to Assess When Selecting Clean Benches And Biosafety Cabinets For Animal Research

Read Abstract

• Many research animals require isolation. In the past, cage-transfer protective equipment was designed primarily to prevent contamination of such animals. While that concern has not diminished, recent events have focused attention on protecting lab workers as well. In some cases, contamination has spread from lab animals to attendants, and in many cases, occupationally-induced asthma has been linked to excessive exposure to animal residue. This paper surveys some of the literature describing passively-transmitted hazards which may be created when they are transferred, or when their cages are cleaned.

Volume 2 No. 2

Using A Constant Air Volume Controller To Insulate A Class II Biosafety Cabinet From Negative Effects of A Variable Air Volume Exhaust System

Read Abstract

• Variable air volume (VAV) systems are often used to exhaust air from chemical fume hoods. VAV controls reduce the exhaust airflow in proportion to the actual need. Consequently the systems uses less fan power, and less energy is used to condition the replacement air.
• Unlike fume hoods, however, biosafety cabinets require a constant flow of air to contain contamination and to protect products in the cabinet. When variable volume fume hoods are connected to the same exhaust system as a biosafety cabinet, the variation in total system exhaust flow can disturb the critical pressure relationships between air flows in the cabinet. Such pressure changes can allow contaminants to escape the cabinet, or allow lab contaminants to enter the cabinet. To avoid these problems, biosafety cabinets can be equipped with constant air volume (CAV) controllers. Such controllers sense flow changes in the cabinet exhaust system. To keep that flow constant, the controller opens or closes a damper located in the cabinet exhaust duct.
• This research shows that CAV controllers can be effective in maintaining constant air flow. However, increases in room supply air can cause local flow turbulence which adversely affect cabinet containment. the test results show that keeping the cabinet airflow constant does not necessarily guarantee that the cabinet will perform properly.

Volume 2 No. 1

Using Thimbles To Connect Biological Safety Cabinets to Variable Air Volume (VAV) Exhaust Systems

Read Abstract

• Variable-volume exhaust systems are a common feature of laboratory ventilation designs. By reducing exhaust airflow in proportion to the actual need, the system uses less energy to condition the make-up air. However, variable exhaust flows can disturb the critical pressure relationships between air flows in biological safety cabinets, which require a constant air flow to maintain performance. Changes in air pressures can allow contaminants to escape the cabinet, or allow lab contaminants to enter the cabinet.
• To avoid these problems, BSC's are often loosely connected to a VAV exhaust system by means of a "thimble", which is in effect an exhaust hood mounted over the cabinet exhaust duct. This loose connection reduces the magnitude of the change in airflow inside the BSC as exhaust air flows fluctuate, so BSC performance is maintained. This paper describes three research projects which investigated the use of thimbles connecting VSC's to VAV exhaust systems. the research results can be useful to designers and end users of laboratory ventilation systems.

Volume 1, No. 2

Cycle Parameters For Decontaminating A Biological Safety Cabinet Using H₂O₂ Vapor

Read Abstract

• Several studies have shown that hydrogen peroxide vapor (H₂O₂) can be useful in decontaminating HEPA filters, isolations chambers and centrifuge enclosures.1-3 However, before hydrogen peroxide can be used reliably in a biological safety cabinet (BSC), it is essential to establish the cycle parameters which allow full decontamination, and which minimize overall cycle time. This paper describes research which established the appropriate physical modifications and decontamination cycle parameters for the Baker Model SG-600, which is a Class II, Type A/B3 biological safety cabinet.

Volume 1, No. 1

Using Hydrogen Peroxide Vapor To Decontaminate Biological Safety Cabinets

Read Abstract

• Recent research has shown that hydrogen peroxide vapor (H₂O₂) can be used to decontaminate biological safety cabinets (BSC's) as an alternative to formaldehyde or ethylene oxide. 1,2,3 H₂O₂ is non-carcinogenic, highly effective as a decontaminant and is environmentally benign. However, H₂O₂ vapor decomposes quickly, so the gas must be rapidly circulated throughout the BSC. Also, hydrogen peroxide vapor attacks some materials. Consequently, existing cabinets need physical changes and material substitutions so the potential advantages of H₂O₂ can be fully realized.