Gas Requirements And Purity; Cryogen Requirements - Micromeritics GEMINI VII KEYPAD Operator's Manual

1 Analyzer Components
G R
AS EQUIREMENTS AND
Improper handling, disposing of, or transporting potentially hazardous materials can
cause serious bodily harm or damage the instrument. Always refer to the MSDS when
handling hazardous materials. Safe operation and handling of the instrument,
supplies, and accessories is the responsibility of the operator.
Compressed gases are required for analyses. Gas cylinders or an outlet from a central source
should be located near the analyzer.
Appropriate two-stage regulators which have been leak-checked and specially cleaned are
required. Pressure relief valves should be set to no more than 30 psig (200 kPag). All gases
should be of a purity listed below. Gas regulators can be ordered from Micromeritics. Parts and
accessories can be found online at www.Micromeritics.com.
When helium is used for differential free-space measurement and nitrogen is used as the
adsorbate gas, they should be of the following purity or better:
Helium — purity of 99.9%. For analysis of materials with very low surface areas, Micromeritics
n
recommends use of helium with purity of 99.995%. (CGA 580)
Nitrogen — purity of 99.9%. For analysis of materials with very low surface areas, Micromeritics
n
recommends use of nitrogen with purity of 99.995%. (CGA 580)
C R
RYOGEN EQUIREMENTS
Liquid nitrogen is commonly used as the cryogen to cool the sample during analysis. A liquid
nitrogen transfer system eliminates the need to pressurize storage Dewars. The Model 021 liquid
nitrogen transfer system is available from Micromeritics (www.Micromeritics.com).
Improper handling, disposing of, or transporting potentially hazardous materials can
cause serious bodily harm or damage the instrument. Always refer to the MSDS when
handling hazardous materials. Safe operation and handling of the instrument,
supplies, and accessories is the responsibility of the operator.
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URITY
Gemini VII Keypad Operator Manual
239-42801-01 (Rev E) — July 2021