SYSTEM DESIGN INFORMATION
26
4.8.2
USE OF FIRE TEST DATA
It has been explained in Sections 4.5 and 4.6 that the sensitivity of the detector is most easily
specified in terms of its response to well-defined test fires. Tests are conveniently carried out using
a 0.1m
2
pan. Sensitivity to other pan areas is estimated from field trial results.
4.8.3
DETERMINING THE NUMBER OF DETECTORS
It will be clear that the number of detectors required for a particular risk will depend on the area
involved and the fire size at which detection is required. Large areas or small fires require large
numbers of detectors.
There are as yet no agreed ‘rules’ for the application of flame detectors and the overall system
sensitivity must, therefore, be agreed between the installer and the end user. Once this agreement
has been reached the system designer can determine the area covered by each detector using a
scaled plot based on Figs. 20 and 21 and the fire test data. This plot is best drawn to the same scale
as the site plan so that direct superposition can be used to determine detector coverage.
In carrying out the design, certain factors should be kept in mind:
a) Mounting the detectors on the perimeter of the area and pointing into the area will
give the best coverage for area rather than spot protection.
b) As the FV300 detectors are line of sight detectors any object within the detector’s
field of view will cause a ‘shadow’ in the protected area. Even small objects close
to the detector can cause large shadows.
c) The detector should not be mounted in such a position that water will collect on
the window.
d) The detectors are passive devices and will not react with one another. They may
therefore be positioned with their fields of view overlapping.
4.9
APPROVALS, COMPLIANCE WITH STANDARDS AND PATENTS
4.9.1
FLAMEPROOF CERTIFICATION
All models of the FV300 FlameVision detectors are flameproof and are certified to the ATEX
directive and IECEx by Baseefa.
The detectors are designed to comply with EN60079-0: 2006, EN60079-1: 2004, EN60079-
7:2006, IEC61241-0: 2006 and IEC61241-1: 2004.
They are certified:
ATEX code:
II 2 G D
Certificate: Baseefa07ATEX0178X
IECEx/Cenelec code: Ex d IIC Ex t D A21 IP66 (-40°C
≤
Ta
≤
+80°C)
or T5 (-40°C
≤
Ta
≤
+70°C)
Certificate:
BAS07.0048X
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