The most recent edition of CBRNe WORLD Magazine includes a highly informative article on the rationale for the procurement and deployment of mobile laboratories. The article, authored by Monica Heyl, discusses the use of mobile labs by first responders, military, law enforcement and civil support teams.  Ms. Heyl describes a range of applications for these units:

“Mobile laboratories can be integrated to fill a wide variety of challenges: sample receipt, screening and evaluating suspect unknown materials, environmental health protection and remediation, narcotics analysis and confirmation of clandestine laboratories. They can respond to catastrophes, terrorism, and a myriad of other actions in theatres of conflict or on our own homelands.” 

The CBRNe World article also discusses the critical role of proper engineering controls in mobile laboratories, stating that:

“Engineering controls (primary and secondary) become vital to sample collection, reception, preparation, analysis and spent effluent that could contaminate the environment. Robust engineering controls to include redundant and hybrid filtration systems, breakthrough monitors and backup uninterrupted power are only as good as the quality assurances associated with the development, building, manufacturing and testing of such safeguards.”

The article, “Mobile Laboratories: Do They Know Their Rank,” by Monica Heyl is available in the Spring 2010 edition of CBRNe World Magazine.

*    *    *

Monica Heyl is an internationally recognized mobile laboratory expert.  She Co-founded,  Monica Heyl and Associates after retiring from the United States Department of Defense, US Army. This firm specializes in field analytical solutions particularly in high hazard environments. Her 35 years of service included a range of leadership positions, including: US Army Senior Leader; Director of International Programs and Leader of the US Army’s Mobile Laboratory & Kits (ML&K) Team and the Advanced CBRNE Training Team.

*    *    *

 CBRNe World  is a internationally distributed quarterly publication based in the UK. The magazine is geared for professionals in a range of fields where their work involves “planning for or responding to a chemical, biological, radiological, nuclear or explosives (CBRNe) threat or incident.”  According to the publishers, the CBRNe World content spans the “divide of operational and scientific, it brings together opinion formers from the world of civil response, military leaders, academia, government agencies, research labs and industry.”

Class III Biological Safety Cabinets: Importance of Hands-on Training

Practical training is particularly useful for students that plan to work in high containment situations. While many students have access to Class II Biosafety Cabinets, too few are able to get hands-on experience with a Class III Biological Safety Cabinet. Class III BSC’s require a familiarization with a wide range of equipment features and configurations such as: Gloves & Gloveports, Pass-throughs / Airlocks, Rapid Transfer Ports, Autoclaves, Decontamination Systems, etc.

Class III BSC Demo

Germfree maintains a Class III BSC training unit at their headquarters. Germfree also participates in student training programs with other facilities, providing institutions with Class III BSC’s and other bio-containment equipment to give their students hands-on experience and training in proper technique.  For example, Germfree’s Biological Safety Cabinets have been used for training in university settings such as The Emory University Science and Safety Training Program as well as workshops in conference settings such as ABSA’s Annual Biological Safety Conference.   

Cliff Colby Demonstrating a Class III Biosafety Cabinet

*     *     *

Cliff Colby is VP of Sales at Germfree. He has more than 12 years experience as a Biosafety Instructor. He has also worked extensively on multi-media biosafety training materials. And if you want to discuss applications that require chemical containment, his background as a Chemist will also come in handy.

*     *     *

 The BioTechnical Institute of Maryland  provides training for students that want to enter the biotech field.  According to the BTI website, the institute ”fills a need for specialty scientific training of entry-level biotechnicians for employment in Maryland’s rapidly expanding biotechnology industry.  The BTI Laboratory Associates Program provides tuition-free training in basic laboratory skills to bright, ambitious, unemployed and under-employed Maryland residents. ”

Class III BSC: Performance Testing Standards

There are several prominent industry accepted standards for performance testing of Class III Biosafety Cabinet in the US.  These standards contain some areas of overlap, and in many cases one standard contains performance related information not contained in the other standards.  The information below provides a brief summary of the highlights as they apply to criteria for US performance testing.  A subsequent blog will address international performance standards.

1. National Sanitation Foundation Standard 49, 2008:

• It is a gas-tight (no leak greater than1×10-7 cc/sec with 1% test gas at 3 inches pressure wg) enclosure with a viewing window that cannot be opened without the use of tools or locks.
• Access for passage of materials into the cabinet is through a dunk tank, that is accessible through the cabinet floor, or double-door pass-through box (e.g., an autoclave, rapid transfer port, pass through chamber)
• Both supply and exhaust air are HEPA filtered on a Class III cabinet. Exhaust air must pass through two HEPA filters, or a HEPA filter and an air incinerator, before discharge to the outdoors.
• Airflow is maintained by an exhaust system exterior to the cabinet, which keeps the cabinet under negative pressure (minimum of 0.5 inches of water gauge.)
• The exhaust fan for the Class III cabinet is generally separate from the exhaust fans of the facility ventilation system.

 2. American Glovebox Society, 2007 :

•  Airflow monitoring: should be provided i.e. magnahelic guage
• Differential pressure is industry specific: maintained at 0.2-1.5 inches wg
• Glovebox flow rate through an open glove port: 125 +/- 25 linear ft/min
• Glove inspections should be performed: no firm guidance on frequency
• Leak detection: internal pressure is stabilized at -1.5 inches wg and temperature, pressure and time are recorded until pressure drops to -0.6 inches.  Leak rate can not exceed 0.5% glovebox volume per hour.
• There should be qualified trainers and operator training.

3.  Laboratory Safety Monograph: A Supplement to NIH Guidelines for Recombinant DNA Research, 1979:

• The Class III biological safety cabinet is a totally enclosed ventilated cabinet of gastight construction.
• Class III cabinet is maintained under negative air pressure of at least 0.5 inches water gage. Supply air is drawn into the cabinet through HEPA filter. The cabinet exhaust air is filtered by two HEPA filters installed in series.
• The exhaust fan for the Class III cabinet is generally separate from the exhaust fans of the facility ventilation system.
• Material transfer through double-door sterilizers and dunk baths with liquid disinfectants.
• Should be certified (i) after a new cabinet has been purchased and installed, but before it is used, (ii) after it has been moved or relocated, and (iii) at least annually.
• Negative pressure inches wg: >0.05
• Leak tightness:  leak rate <1 x 10 ^-5 cc/sec at 3”wg pressure using halide tracer gas
• Small leaks can be detected by soap solution testing
• HEPA certification: annual or as needed above
• Verify and calibrate magnahelic gauge and test audible alarm

Class III BSC:  Best Safety Practices & Engineering

Taken together there are a few recurrent points and statements that reflect best safety practices and engineering.  The Class III Biological Safety Cabinet must be leaktight (this implies very solid construction, durability and seals), and operate at -0.05 ” wg relative to the lab.  Exhaust air is filtered through 2 HEPA filters in series, with supply air filtered by 1 HEPA filter.  Alarms should be present to warn the user of BSC failure, and the user should be trained in te correct operation of the unit.  The BSC and its HEPA filters should be field tested annually, but components that are prone to wear (i.e. gloves, gaskets, etc) should be inspected as part of a pre-operational inspection.  As perfromance tests in the field are not codified by NSF 49, recomendations on what types of field testing should be perfromed annually will be provided in a later blog.

References:

1. NSF 49 Class II (Laminar Flow) Biosafety Cabinetry, NSF/ANSI 49-2008,  Edition: 11th

2. Guideline For Gloveboxes, Third Edition AGS-G001, February 2007

3.  Laboratory Safety Monograph: A Supplement to the NIH Guidelines for Recombinant DNA Research, 1979 (PDF)

Dallas, Tx
Hilton Anatole
Booth #704
http://www.nhia.org/ac10/