Information Notice No. 95-48: Results of Shift Staffing Study

                                 UNITED STATES
                         NUCLEAR REGULATORY COMMISSION
                          WASHINGTON, D.C. 20555-0001

                               October 10, 1995



All holders of operating licenses or construction permits for nuclear power


The U.S. Nuclear Regulatory Commission (NRC) is issuing this information
notice to inform addressees of the results of the NRC's study conducted as
part of an NRC Office of Nuclear Regulatory Research (RES) project to address
the adequacy of minimum shift staffing levels at nuclear power plants (NPPs). 
It is expected that recipients will review the information for applicability
to their facilities and consider actions, as appropriate, to avoid similar
problems.  However, suggestions contained in this information notice are not
NRC requirements; therefore, no specific action or written response is

Description of Circumstances

On November 26, 1991, the NRC issued IN 91-77, "Shift Staffing at Nuclear
Power Plants," (Reference 1) to alert licensees to the problems that could
result from inadequate controls to ensure that shift staffing is sufficient to
accomplish all functions required by an event.  However, after IN 91-77 was
issued, event follow-up inspections indicated that problems involving shift
staffing and task allocation continued to occur.  

As a result, the NRC continued with further research in this area.  This
research included an NRC RES project to address the adequacy of minimum shift
staffing levels through a shift staffing study encompassing all licensee staff
initially needed during an event.  

The first component of the shift staffing study (Reference 2) included an
evaluation of the experience and events for which staffing was a contributing
factor and the identification of the primary issues related to NPP shift
staffing levels.  Particular attention was given to shift staffing concerns
expressed in recent inspection reports.  The corresponding events typically
occurred at power during the backshift.  In addition, observation of emergency
preparedness exercises showed that the potential for work overload appeared to
be higher among senior reactor operators and shift supervisors than among
reactor operators.  Dominant factors identified in the study were task
allocation and location (including fire brigade support), procedure design,
human-system interface, training, and communications.   

9510040181.                                                            IN 95-48
                                                            October 10, 1995
                                                            Page 2 of 3

The second component of the shift staffing study (Reference 3) consisted of
detailed, on-site data collection and assessment of the adequacy of current
NPP staffing practices for performing activities necessary for responding to
and mitigating events.  This effort was accomplished by a team survey of the
staffing practices at seven NPPs.  The two-person research teams, having both
operational and human factors expertise, gathered information on site from
seven voluntary participants representing the four vendor types, the four NRC
regions, single and multi-unit sites, and a variety of plant ages.  The teams
used four methods of collecting data:  (1) plant documentation review, 
(2) table-top talk-throughs of two accident scenarios (a fire leading to a
reactor trip with complications and either a control room fire leading to
evacuation and remote shutdown or a station blackout), (3) outside control
room walk-throughs of specific tasks related to the scenarios, and (4)
interviews with site personnel from different groups and levels.  Findings of
the second component of the study were the following:

.     The licensees surveyed did not use a systematic process for establishing
      site-specific shift staffing levels.

.     The licensees surveyed frequently assigned additional plant-specific
      tasks that were not specified by regulation to be performed by licensed
      and non-licensed personnel during an event.

.     Five of the licensees surveyed used licensed personnel to staff the fire
.     The administrative procedures of the licensees surveyed varied
      significantly in both the licensed and non-licensed personnel shift
      staffing levels and the types of positions staffed.  In addition, the
      number of non-licensed operators normally used during the backshift
      varied greatly. 

.     The radiation protection and chemistry technicians of all the licensees
      surveyed had a high workload during the scenarios. 

.     During scenario talk-throughs, similar-vendor licensees made
      significantly different decisions, resulting in very different control
      room activities and in-plant tasks.

.     The licensees surveyed were actively engaged in efforts to reduce
      operating and maintenance costs, which could result in a reduction in


As stated in IN 91-77, "The number of staff on each shift is expected to be
sufficient to accomplish all necessary actions to ensure a safe shutdown of
the reactor following an event.  Those actions include implementing emergency
operating procedures, performing required notifications, establishing and
maintaining communications with the NRC and plant management, and any
additional duties assigned by the licensee's administrative controls.... 
Section 50.54(m) of Title 10 of the Code of Federal Regulations .                                                            IN 95-48
                                                            October 10, 1995
                                                            Page 3 of 3

addresses only minimum staffing levels for licensed personnel and does not
address personnel availability for performing all of the necessary actions
specified in the licensee's administrative controls and required by an event."

The licensees surveyed generally staffed to levels greater than those required
by either the regulations or their plant-specific technical specifications for
both licensed and non-licensed personnel.  Nevertheless, the results of the
research project described in this IN provide several insights into areas
which could impact the ability to accomplish safety functions following an

This information notice requires no specific action or written response.  If
you have any questions about the information in this notice, please contact
one of the technical contacts listed below or the appropriate Office of
Nuclear Reactor Regulation (NRR) project manager.

                                    /s/'d by BKGrimes/for

                                    Dennis M. Crutchfield, Director
                                    Division of Reactor Program Management
                                    Office of Nuclear Reactor Regulation


1.    NRC Information Notice 91-77, "Shift Staffing at Nuclear Power Plants,"
      November 26, 1991.

2.    D. Shurberg et al., "Identification of Issues Associated with Nuclear
      Power Plant Shift Staffing Levels," Task 1 Letter Report, Brookhaven
      National Laboratory, July 20, 1994.  (Accession No. 951003074)

2.    S. Haber et al., "Nuclear Power Plant Shift Staffing Levels: Site Data
      Collection Report," Letter Report, Brookhaven National Laboratory,
      February 1995.  (Accession No. 9510030160)

Technical contacts:  Jesse Arildsen, NRR        David Desaulniers, NRR
                     (301) 415-1026             (301) 415-1043

                     Neal Hunemuller, NRR
                     (301) 415-1152

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