U.S. Nuclear Regulatory Commission

Guidance on Test conditions for Activated Charcoal Using Methyl Iodide

HPPOS-069 PDR-9111210156

Title: Guidance on Test conditions for Activated Charcoal

Using Methyl Iodide

See the letter from W. Gammill to F. D. Leckie (Nuclear

Containment Systems, Inc.) dated September 24, 1981.

Guidance was provided on test conditions for activated

charcoal using methyl iodide. Technically, the best

approach is to use ANSI N509-1980, since it is an update

and refers to the latest industry-approved test procedures.

Guidance was requested on Regulatory Guide 1.52 for used

carbon, as to the proper temperature, relative humidity and

the allowable percent penetration. NRC replied that plant

Technical Specifications are the over-riding and

controlling document. If the Technical Specifications list

specific conditions, the test must be performed under those

conditions. If some, but not all conditions are specified,

then the ASTM procedures in ASTM D3803-1979 "Standard Test

Methods for Radioiodine Testing of Nuclear-Grade Gas Phase

Adsorbents" should be used to satisfy the remaining

conditions. If the Technical Specifications refer to

Regulatory Guide 1.52, Revision 2, March 1978, then page 6

of the document provides the proper course of action.

Technically however, the best course of action is to follow

ANSI N509-1980, since it is an update and refers to the

latest industry approved test procedures (ASTM D3803-1979).

Regulatory references: ANSI N509-1980, ASTM D3803-1979,

Regulatory Guide 1.52, Technical Specifications

Subject codes: 5.4

Applicability: Reactors