Standard No.:	GB 15146.7-1994
English Name:	Nuclear criticality safety for fissile materials outside reactors－Safety controls in conducting subcritical neutron multiplication measurements in situ
Chinese Name:	反应堆外易裂变材料的核临界安全 次临界中子增殖就地测量安全规定
Chinese Classification:	F09    Hygiene, safety and labor protection
Professional Classification:	GB    National Standard
ICS Classification:	27.120.30 27.120.30    Fissile materials and nuclear fuel technology 27.120.30
Source Content Issued by:	State Technical Supervision Bureau
Issued on:	1994-07-07
Implemented on:	1995-1-1
Status:	valid
Target Language:	English
File Format:	PDF
Word Count:	2500 words
Translation Price(USD):	115.0
Delivery:	via email in 1 business day

Nuclear criticality safety for fissile materials outside reactors - Safety controls in conducting subcritical neutron multiplication measurements in situ 1 Subject content and application scope This standard specifies the safety requirements and implementation rules for neutron multiplication measurements in situ of subcritical fissile assembly. This standard is applicable to the neutron multiplication measurements in situ of subcritical fissile assembly; it shall also be used for reference purpose for measurements in situ of other reactivity indexes of subcritical fissile assembly. 2 Terms 2.1 fissile assembly (assembly) system consisting of fissile material and other components that influence the reactivity 2.2 reactivity quantity that characterizes the degree to which a fissile assembly deviates from a critical state, which is proportional to (keff-1)/keff, where keff is the effective multiplication factor for the assembly; the reactivity of a critical assembly is zero; the reactivity of a subcritical assembly is a negative quantity indicating the degree of subcriticality 2.3 neutron multiplication (multiplication) for the purpose of this standard, it signifies a neutron counting rate that is sensitive to reactivity change of a fissile assembly and often normalized (or corrected) to the counting rate that would result if there were no fissions 2.4 reactivity index parameter (such as the prompt neutron decay constant) that can characterize the reactivity of an assembly or from which the reactivity of the assembly can be deduced

1 Subject content and application scope 2 Terms 3 Administrative requirements 4 Equipment criteria 5 Implementation rules