Camfil Farr has developed partnerships with the leading biosafety and laminar flow cabinet manufacturers over many years. We are highly familiar with the technical requirements for this industry. The HEPA filter of choice for the industry is the MEGALAM.
MEGALAM
Our renowned MEGALAM filter allows the OEM to maximize airflow and reduce pressure drop, thus reducing significant energy costs depending on the filter pack depth selected.
When unidirectional airflow is a must:
Safety Cabinets are known for their high requirements in terms of laminarity. Some of our OEM customers have requested as low as 0.45 m/s / 90 fpm ± 10%. Thanks to our Controlled Media Spacing (CMS), pleating technology and optional ‘laminator’ applied to the filter pack during production, we can meet these exacting demands.
Complete Range of HEPA Filters
Our MEGALAM filters are manufactured in three standard depths: 45, 68 and 90 mm (nominal 2, 3 and 4" packs). All filters supplied are individually tested with full traceability to consistently deliver ultra-clean, cost-effective air for the most demanding environments.
Standards relating to laboratories:
1. EN 12469 Safety Cabinet Standard
Three classes of safety cabinets:- Class I: Safety cabinet with a front aperture through which the operator can carry out manipulations inside the cabinet, which is constructed so that the worker is protected and the escape of airborne particulate contamination generated within the cabinet is controlled by means of an inward air flow through the working front aperture and filtration of the exhaust air.
- Class II: Safety cabinet with a front aperture through which the operator can carry out manipulations inside the cabinet, which is constructed so that the worker is protected, the risk of product and cross contamination is low and the escape of airborne particulate contamination generated inside the cabinet is controlled by means of an appropriate filtered internal air flow and filtration of the exhaust air. Note: A typical way of achieving this is by means of a uni-directional downward (laminar) air flow inside the cabinet and an air curtain at the front aperture.
- Class III: Safety cabinet in which the working area is totally enclosed and the operator is separated from the work by a physical barrier (i.e. gloves mechanically attached to the cabinet). Filtered air is continuously supplied to the cabinet, and the exhaust air is treated to prevent release of microorganisms.
2. WHO Biosafety Manual
Designed to prevent exposure to harmful microorganisms, this document establishes risk levels from 1 to 4, with risk level 1 the minimum and risk level 4 the maximum. Levels 1 and 2 are not regarded as containment laboratories, whereas levels 3 and 4 are. Codes of Practice address access, personal protection, procedures, working areas and biosafety management. Design and Facilities addresses design features. Laboratory equipment addresses essential biosafety equipment. Health and Medical Surveillance addresses the monitoring of workers handling microorganisms of varying risk levels. Training, waste handling, and chemical, fire, electrical and radiation safety are also covered.
Excerpts from the manual:
The containment laboratory – Biosafety Level 3 is designed and provided for work with Risk Group 3 microorganisms and with large volumes or high concentrations of Risk Group 2 microorganisms that pose an increased risk of aerosol spread. Biosafety Level 3 containment requires the strengthening of the operational and safety programmes above those for basic laboratories – Biosafety Levels 1 and 2. (1)
1. The building ventilation system must be constructed so that air from the containment laboratory – Biosafety Level 3 is not recirculated to other areas inside the building. Air may be HEPA filtered, reconditioned and recirculated inside that laboratory. Exhaust air from the laboratory (other than from biological safety cabinets) must be discharged to the outside of the building, so that it is dispersed away from occupied buildings and air intakes. It is recommended that this air is discharged through high-efficiency particulate air (HEPA) filters. (1)
2. Biological safety cabinets should be sited away from walking areas and out of cross-currents from doors and ventilation systems (see Chapter 7). (1)
3. Exhaust air from Class I or Class II biological safety cabinets (see Chapter 7) that has passed through HEPA filters must be discharged so as to avoid interference with the air balance of the cabinet or the building's exhaust system. All HEPA filters must be installed in a manner that permits gaseous decontamination and testing. (1)
The maximum containment laboratory – Biosafety Level 4 is designed for work with Risk Group 4 microorganisms. Before such a laboratory is constructed and put into operation, intensive consultations should be held with institutions that have experience of operating this type of facility. Operational maximum containment laboratories – Biosafety Level 4 should be under the control of national or other appropriate health authorities. (1)
1. Controlled air system. Negative pressure must be maintained in the facility. Both supply and exhaust air must be HEPA-filtered. There are significant differences in the ventilating systems of the Class III cabinet laboratory and suit laboratory:
- Class III cabinet laboratory. The supply air to the Class III biological safety cabinet(s) may be drawn from within the room through a HEPA filter mounted on the cabinet or supplied directly through the supply air system. Exhaust air from the Class III biological safety cabinet must pass through two HEPA filters prior to release outdoors. The cabinet must be operated at negative interim guidelines pressure to the surrounding laboratory at all times. A dedicated non-recirculating ventilating system for the cabinet laboratory is required.
- Suit laboratory. Dedicated room air supply and exhaust systems are required. The supply and exhaust components of the ventilating system are balanced to provide directional air flow within the suit area from the area of least hazard to the area(s) of greatest potential hazard. Redundant exhaust fans are required to ensure that the facility remains under negative pressure at all times. The differential pressures within the suit laboratory and between the suit laboratory and adjacent areas must be monitored. Air flow in the supply and exhaust components of the ventilating system must be monitored and an appropriate system of controls must be used to prevent pressurization of the suit laboratory. HEPA-filtered supply air must be provided to the suit area, decontamination shower and decontamination airlocks or chambers. Exhaust air from the suit laboratory must be passed through a series of two HEPA filters prior to release outdoors. Alternatively, after double HEPA filtration, exhaust air may be recirculated, but only within the suit laboratory. Under no circumstances may the exhaust air from the Biosafety Level 4 suit laboratory be recirculated to other areas. Extreme caution must be exercised if recirculation of air within the suit laboratory is elected. Consideration must be given to the types of research conducted, equipment, chemicals and other materials used in the suit laboratory, as well as animal species that may be involved in the research. (1)
All HEPA filters need to be tested and certified annually. The HEPA filter housings are designed to allow for in situ decontamination of the filter prior to removal. Alternatively, the filter can be removed in a sealed, gas-tight primary container for subsequent decontamination and/or destruction by incineration. (1)
(1) Laboratory Biosafety Manual, World Health Organization, 2003