Spectrex Xenon 700 SIL Open-Path Gas Detection System - Manual (Page 42)

SafEye TM Xenon 700S SIL Gas Detector
30 Preparations for Installation
5.2.3 Site Requirements
The installation position of the SafEye system must take into account if the
gas being monitored is heavier or lighter than air, and the individual site
requirements. The site selected must give the Detector a direct view to the
Source. The mounting point for each item should be secure and stable with
minimal vibrations. Equipment should be either mounted in a position where
it cannot be knocked out of alignment, or guarded from physical impact.
5.2.4 The Source and Detector
The appropriate Detector should be selected for the length of open path to
be monitored. To allow for ageing of the Source and a reduction of the IR
signal due to adverse weather we recommend using a Detector that is not at
the limit of its operating range. As a guide, select a Detector that is installed
at a distance from the Source of not more than 75% of the specified
operating distance. In severe weather conditions such as offshore oil
production and exploration, this should be reduced to 50%.
The open path between the Source and Detector and the immediate
surroundings should be kept clear of obscuration that might hinder the free
movement of air in the protected area or block the infrared beam.
5.2.5 Guidance Tips for Gas Detector Locations
Guidance Tips for Gas Detector locations in order to provide the best
detection coverage:
 Below potential leak source for heavier than air gases
 Above potential leak sources for lighter than air gases
 Near to leak sources along the expected leak trajectory, taking into
account prevailing wind directions
 Between leak source and potential ignition sources
 In area with expected heavy fog, rain or snow, consider the effect of
long range installation and install the Detector at shorter range with the
maximum intensity model available.
5.3 Preparations for Installation
Installation should comply with local, national and international regulations
and norms as applicable to gas Detectors and approved electrical devices
installed in hazardous areas. The Detectors can be installed with general-
purpose common tools and equipment.
The System should include the following (in addition to this manual):
 Detector unit: XDSS-C-11XXX (See Models and Types on page 9)
 Source unit: XSS-C-XX (See Models and Types on page 9)