6/19/2015 BIOLOGICAL SAFETY CABINET. Types of Classes. Types of BSC.

Transcription

1 Biosciences eastern and central Africa International Livestock Research Institute (BecA ILRI) Hub Mobilizing biosciences for Africa s development Laboratory Management and Equipment Operations Workshop. Rwanda Agricultural Board. (RAB)-Rubona Station. 15 th -19 th June BecA ILRI Hub Nairobi, Kenya June, 2015 SAM CHIERA. BIOLOGICAL SAFETY CABINET. BIOLOGICAL SAFETY CABINET - INTRODUCTION. This is an enclosed, ventilated laboratory workspace. Mainly used for safely working with materials contaminated with pathogens (anything that can cause/produce disease). It is usually in a negative pressure for containment purpose. Types of BSC. BSC are classified in three classes. They are categorized in three ways of protection. Level of personnel protection. Level of environmental protection Level of product protection. Types of Classes. Class I. Class II. Class III. 1

2 Classifications. Class 1. Classification Biosafety Level Application low to moderate risk Class I 1, 2, 3 biological agents Class II 1, 2, 3 low to moderate risk biological agents Class III 4 high risk biological agents Class I. cabinets provide personnel protection but no product protection and environmental. this class are either ducted (connected to the building exhaust system) or unducted (recirculating filtered exhaust back into the laboratory). BSC-CLASS I. Class II Class II cabinets provide both kinds of protection of the samples and of the environment. makeup air is also HEPA filtered (High Efficiency Particulate Air). These are further classified as Type A1,Type A2,Type B1,Type B2. Each type's requirements are defined by NSF International Standard 49. BSC-CLASS II Type A1 (class II). The Type A1 cabinet has a minimum inflow velocity of 75 ft./min. The filtered makeup air is divided equally over the work surface at about two to six inches above the work surface. Exhaust is drawn at the bottom of the cabinet where it rises to the top. At the top of the cabinet, 70% of the air recirculates through the supply HEPA filter, the other 30% of air exhausted through the exhaust HEPA filter. 2

3 BSC-CLASS II TYPE A I Type A 2 (class II). Has a minimum inflow velocity of 100 ft/min. A negative air pressure plenum surrounds all contaminated plenums that are under positive pressure. BSC-CLASS II TYPE A II Type B1 (class II). The Type B1 cabinets have a minimum inflow velocity of 100 ft/min. These cabinets must be hard ducted to an exhaust system( In contrast to the type A1 and A2 cabinets, 60% of air from the rear grille is exhausted and only 40% is recirculated). BSC-CLASS II TYPE B I Type B2 (class II). Type B2 cabinets have a minimum inflow velocity of 100 ft/min Type B2 cabinet is expensive to operate because no air is recirculated within. this type is mainly found in such applications as toxicology laboratories. cabinets of these types generally monitor the exhaust flow, shutting off the supply blower and sounding an alarm if the exhaust flow is insufficient. 3

4 BSC-CLASS II TYPE B II Class III. Class III cabinet, generally only installed in maximum containment laboratories. Specifically designed for work with BSL 4 pathogenic agents, providing maximum protection (A pathogen is anything that causes a disease). The enclosure is gas tight. All materials enter and leave through a dunk tank or double door autoclave. Cont. BSC-CLASS III. Gloves attached to the front prevent direct contact with hazardous materials. These cabinets are sometimes called glove box. Provide a physical barrier between biological agents and personnel. BSC- CLASS III Biological Safety Cabinet Testing & Validation. 4

5 Certification. When. A Biological Safety Cabinet MUST be certified. must be performed by experienced, qualified personnel. On-site testing following the recommendations for field testing [NSF/ANSI Initial Installation. Moved or Relocated. After a Major Repair. Annually. Types of tests. Types of certificates. down flow velocity. inflow velocity. airflow smoke patterns. filter leak. light intensity. Vibration. noise level UV light integrity Thank you Samuel Gakuha Chiera Engineering Technician ILRI Nairobi Kenya Engineering Department s.chiera@cgiar.org Mobilizing biosciences for Africa s development 5