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USER SECTION
CHAPTER 3 – INSTALLING YOUR CABINET
3.4 INSTALLATION LOCATION EXTRACTED FROM BS 7258
The following article is Esco recommendation extracted from
British Standard BS 7258- PART 2:1994:
To avoid disturbances to the fume cabinet and its operator, consideration should be given to the
following:
a) The distance from the plane of the aperture to any circulation space should be at least 1000 mm,
so as to preserve a zone undisturbed by anyone other than the operator – see figure 1a.
b) The distance between the front aperture and a bench opposite it should ideally be at least 1500
mm – see figure 1b. However, containment performance is not likely to be affected if this
distance is reduced, for instance to enable an operator to use the bench behind whilst working at
the cabinet. In this case operator movement over a smaller distance may cause less air
disturbance. With such procedures their effect on containment should be measured by relevant
operator protection factor tests.
c) There should be no opposing wall (or other obstruction likely to affect the airflow) within 2000
mm of the front aperture – see figure 1c.
d) Cabinets should not be installed in positions where they are likely to be affected by other items
or equipment. In particular the distance to the aperture of an opposing cabinet, or the edge of a
local exhaust ventilation outlet should be not less than 3000 mm – see figure 1d.
e) Any room air supply diffuser should not be within 1500 mm of the front aperture. If there are
large numbers of safety cabinets in a laboratory this recommendation may be difficult to comply
with, but where diffusers have to be placed in close proximity to a cabinet, their discharge
velocities and therefore air handling rates will need to be low.
f) A cabinet should not be positioned with either side closer than 300 mm from a wall or similar
obstruction – see figure 1e.
g) Large obstructions (e.g. and architectural column) projecting beyond the plane of the aperture
should not be within 300 mm of the side of the fume cabinet – see figures 1f and g.
h) Doorways should not be within 1500 mm of the aperture or within 1000 mm of the side of the
fume cabinet – see figure 1h – except where a door includes air transfer grills in which case
protection factor testing should be carried out to ascertain a suitable distance.
The position of a cabinet should satisfy the spatial requirements (e.g. vision, lighting and convenience of
access) of the operator and personnel working nearby. When a cabinet is installed on a bench top, the
leading edge should be flush with or slightly overhanging the edge of the bench top.
Note 1: Typical problems and their solutions are illustrated in figure 2.
Note 2: There should not be an open space between the leading edge of the cabinet and the front of the
bench as this may create turbulence in front of the aperture. It also provides an obstacle which could
adversely affect airflow across the cabinet face.
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Содержание ASCENT OPTI BASIC
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