Conclusion - ABB MR Series Startup Procedure

humidity of 65% as the material still retains a cooler dew point temperature level until it is able to warm to the
ambient temperature or above the ambient temperatures for safer exposure.
The recommended level of relative humidity, for safe exposure of hygroscopic optical materials, is typically
35% as specified by various suppliers of the materials. From levels of 35 - 100 % relative humidity, the materials
will absorb more water vapor to the point of condensation onto the surface at 100% RH. In this light, it is
apparent that the relative humidity must be maintained as specified in order to preserve any optical materials
susceptible to moisture damage.
e. CONCLUSION
In most cases of optical material failure, the cause has been due to fogging of the component due to exposure to
moisture. Such problems can be eliminated by following the guidelines as laid out in this document.
The rule of thumb to be followed is that the relative humidity should remain below 35% at all times to preserve
the quality of the hygroscopic optical materials. Care should be taken in the storage, handling, and transport of
such materials, but this does not require much effort if some simple practices as outlined are implemented.
Possible sources for desiccant materials:
Les Entreprises James Dawson
Montreal, CANADA
(514) 637-6721
Humidial Corp.
465 N. Mt. Vernon Ave.
PO Box 610
Colton, California 92324, USA
(714) 825-1793
United Desiccants-Gates
6845 Westfield Ave.
Pennsauken, NJ 08110-1582, USA
(609) 662-6500
Possible source for heat-sealing equipment:
National Instrument Co.
4119 Fordleigh Rd.
Baltimore, MD 21215, USA
(301) 764-0900
MR Series FT-Spectroradiometers
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