EuroFlow EF and EF/B
Biological Safety Cabinet
UM-EFAB-EN10.doc
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the measured values should deviate more than 20% from the average value. See
Appendix V:
Measuring method air velocities on page 76
for more specifications.
•
In case HEPA filter Integrity is measured with a photometer and DOP, EMERY 3004 or DEHS as
test aerosol, then the maximum local penetration should not exceed 0,01%.
If the required Integrity cannot be met then it is allowed to repair up to 5% of the surface area
of the HEPA filter.
(Alternative method: In case HEPA filter Integrity is measured with a particle counter then local penetration should
be
≤
0.05%. When the overall Integrity is measured the penetration should not exceed 0,005%).
Exhaust HEPA filter
The HEPA filter needs to be replaced when the HEPA filter integrity is not within specifications
and/or when it is not possible to adjust the air velocity according the specifications.
For the exhaust HEPA filter the following applies:
•
The average velocity of the air inflow should be > 0,50 m/s. The air velocity, measured
perpendicular to the air flow at the top side of the work aperture, should be
≥
0,28 m/s.
•
In case HEPA filter Integrity is measured with a photometer and DOP, EMERY 3004 or DEHS as
test aerosol, then the maximum local penetration should not exceed 0,01%.
If the required Integrity cannot be met then it is allowed to repair up to 5% of the surface area
of the HEPA filter.
(Alternative method: In case HEPA filter Integrity is measured with a particle counter then local penetration should
be
≤
0.05%. When the overall Integrity is measured the penetration should not exceed 0,005%).
The first, V-shaped HEPA filters (EF/B)
The HEPA filter needs to be replaced when the HEPA filter integrity is not within specifications
and/or when it is not possible to adjust the air velocity according the specifications.
For the first, V-shaped HEPA filters (only relevant to the EF/B class II cabinets) the following
applies:
•
The downflow velocity of the cabinet must have an average air velocity of 0,36 +/- 0,02 m/s,
measured at 10 cm above the bottom edge of the sliding window (in work position). None of
the measured values should deviate more than 20% from the average value. See
Appendix V:
Measuring method air velocities on page 76
for more specifications.
•
The average velocity of the air inflow should be > 0,50 m/s. The air velocity, measured
perpendicular to the air flow at the top side of the work aperture, should be
≥
0,28 m/s.
•
In case HEPA filter Integrity is measured with a photometer and DOP, EMERY 3004 or DEHS as
test aerosol, then the maximum local penetration should not exceed 0,01%.
If the required Integrity cannot be met then it is allowed to repair up to 5% of the surface area
of the HEPA filter.
(Alternative method: In case HEPA filter Integrity is measured with a particle counter then local penetration should
be
≤
0.05%. When the overall Integrity is measured the penetration should not exceed 0,005%).
2.
Replacement of HEPA filters
Make sure that the cabinet has been properly decontaminated so as to ensure that no danger
exists for the service engineer, the laboratory personnel and the environment.
If the customer has a special procedure for the disposal of contaminated material, then this should
be followed. In case the service engineer does not think that this is sufficient, then proper
precautions should be made in consultation with the person responsible for the safety cabinet.
If there is no special procedure it is best to wear at least gloves and the protective clothing
normally worn during work with the safety cabinet. It is also advised to have a breathe protection
e.g. with a semi-facial mask with HEPA filters.
