None

PNC TJ1545 96-001, 137 Pages, 1996/03

PNC-TJ1545-96-001.pdf:5.98MB

no abstracts in English

Survey on the behavior of radioactive substance in the atmosphere

*; *; *; Iida, Takao*; *; *

PNC TJ1545 94-003, 39 Pages, 1994/03

PNC-TJ1545-94-003.pdf:1.02MB

no abstracts in English

None

PNC TJ1545 94-001, 82 Pages, 1994/03

PNC-TJ1545-94-001.pdf:3.81MB

no abstracts in English

Survey on the behavior of radioactive substance in the atmosphere

*; *; *; Iida, Takao*; *; *

PNC TJ1545 93-005, 36 Pages, 1993/03

PNC-TJ1545-93-005.pdf:1.09MB

no abstracts in English

None

PNC TJ1545 93-002, 89 Pages, 1993/03

PNC-TJ1545-93-002.pdf:3.03MB

None

Survey on the behavior of radioactive substance in the atmosphere

*

PNC TJ1545 92-005, 51 Pages, 1992/03

PNC-TJ1545-92-005.pdf:1.23MB

no abstracts in English

None

PNC TJ1545 92-003, 187 Pages, 1992/03

PNC-TJ1545-92-003.pdf:6.97MB

no abstracts in English

None

Nuclear Safety Technology Center*

PNC TJ1545 91-002, 120 Pages, 1991/03

PNC-TJ1545-91-002.pdf:3.54MB

no abstracts in English

Study on the effect of environment to the performance of charcoal filters

PNC TJ9545 87-002, 60 Pages, 1987/05

PNC-TJ9545-87-002.pdf:1.46MB

Exhaust gas treatment system installed in a reactor is composed of HEPA filters using glass fibers and charcoal filters for the removal of radioactive iodine. It is requested for the charcoal filters in the periodical inspection to keep the same or better performance as the regulatory criteria, by an efficiency test, since they have been recognized to become inferior gradually in their performance due to aging. The efficiency test of charcoal filters in JOYO has been carried out by using radioactive iodine, which has brought some restrictions on timing of the test and on working environment for the testing. This report sumarizes current testing criteria including frequency of the inspection, new efficiency testing method and new iodine adsorbant materials, as follows. As for current testing criteria, are described outline of iodine treatment, basic concept of catching iodine and method of the inspection and management in commercial power reactors. A new promising efficiency testing method is proposed with an equipment flow diagram which indicates the method for calculating decontamination factor based on analytical values of iodine before and after the filter, by a gas-chromatographic method using non-radioactive methyl iodide. It became clear by the survey that new iodine adsorbant materials contain silver along which alumina and silica gel type are superior compared with famous silver-zeolite. It can be concluded that any adsorbant of this expensive type is not recommended for the use in a reactor, only significant in accidental conditions, however it is superior in its decontamination factor.