Information Notice No. 93-18: Portable Moisture-Density Gauge User Responsibilities During Field Operations

                           UNITED STATES
                      WASHINGTON, D.C.  20555

                          March 10, 1993



All U. S. Nuclear Regulatory Commission licensees that possess moisture-
density gauges.


NRC is issuing this information notice to remind licensees of their
responsibility to maintain constant surveillance and security of portable
moisture-density gauges during field operations.  Failure to adequately secure
gauges at construction sites has resulted in several incidents that have
caused damage to the gauges.  It is expected that recipients will review the
information for applicability to their licensed activities, distribute this
notice to responsible radiation safety staff and gauge users, 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 required.

Description of Circumstances

During the busy construction season, NRC licensees use moisture-density gauges
extensively.  Consequently, more incidents involving gauges occur at this time
than at other times during the year.  Longer working hours, along with an
increase in the number of jobs performed by a licensee, may contribute to the
increase in incidents involving gauges.  Recent incidents show that damage by
heavy construction equipment is frequently a cause of these incidents.

In 1991 and the first three quarters of 1992, NRC was notified about 44
incidents that involved moisture-density gauges.  Sixteen of the incidents
involved gauges that were damaged at temporary job sites.  Although the
devices sustained severe damage, the sources usually remained in the shielded
position within the device.  In many of these cases, the authorized user had
not complied with regulatory requirements for maintaining constant
surveillance and immediate control of the device (10 CFR 20.207). 
Specifically, the authorized user must be in immediate control of the gauge
(10 CFR 20.207) so that he or she can, at all times, prevent damage to, or
misuse of, the gauge.

In one recent incident, a device was severely damaged by the licensee's
transport vehicle.  The impact severed the source rod and dislodged the
source.  The licensee did not immediately follow its own emergency procedures,
and left the source unattended for several hours.  The unencapsulated source 
was found later, at the site, lying on the base rock.  The licensee responded 


                                                      IN 93-18
                                                      March 10, 1993
                                                      Page 2 of 3

by restricting the area and obtaining outside assistance to conduct radiation 
surveys, recover the source, test the source for leakage of radioactive 
material, and package and ship the source for disposal.  The leak test showed
no leakage from the source.  A survey also showed no contamination on the base
rock surface where the source was found, so decontamination operations at the
site were not necessary.  However, recovery was costly and the licensee's
operations were significantly disrupted.  This incident could have been
prevented by simply maintaining constant surveillance of and immediate control
of the device.  In addition, NRC enforcement actions, including civil
penalties, are considered in cases such as this.


When using moisture-density gauges at temporary job sites, the authorized user
must not leave the gauge unattended at any time (10 CFR 20.207(b)).  When
personnel are finished using the device, they must properly secure the
moisture-density gauge (10 CFR 20.207(a)), to prevent damage, loss, or theft. 
One method of complying with the requirements would be to lock the source rod
in the safe storage position, lock the device in its transport container, and
secure the transport container from theft or loss in the licensee's vehicle or
in a storage building.  The requirements for control and security of licensed
material are given in 10 CFR 20.207 or, for licensees implementing the revised
Part 20, Sections 20.1801 and 20.1802.  Properly securing moisture-density
gauges will prevent damage to gauges at temporary job sites.

Many incidents involving gauges have occurred when the authorized user left
the gauge unattended for several moments to get some item (notebook, coffee,
etc.), to return to the transport vehicle, or to speak with someone.  It must
be emphasized that gauge users must not leave the device unattended. 
Temporary lapses in control, however minor, have often resulted in damaged
gauges.  NRC will take enforcement action, possibly leading to civil penalties
(i.e., monetary fines), in such cases.

In addition, it is suggested that licensees conduct periodic training, for all
authorized users, to emphasize proper procedures for use and security of the
gauges.  Licensees should ensure that all personnel understand adequate
emergency response actions and relevant safety topics. An understanding of the
topics in Attachment 1 is essential to safe operations.

Related Generic Communication

The topics in Attachment 1 are covered in the license conditions, the license
application, the regulations, and in the following information notices:

      IN 88-02 "Lost or Stolen Gauges"

      IN 87-55 "Portable Moisture/Density Gauges:  Recent
                Incidents of Portable Gauges Being Stolen or

      IN 86-67 "Portable Moisture/Density Gauges:  Recent
                Incidents and Common Violations of Requirements 
                for Use, Transportation, and Storage"

                                                           IN 93-18
                                                           March 10, 1993
                                                           Page 3 of 3

      IN 84-26 "Recent Serious Violations of NRC Requirements by
                Moisture Density Gauge Licensees"

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 regional

                                        ORIGINAL SIGNED BY

                                    Richard E. Cunningham, Director
                                    Division of Industrial and
                                      Medical Nuclear Safety
                                    Office of Nuclear Material Safety
                                      and Safeguards

Technical contacts:  Thomas Young, RIII
                     (708) 790-5182

                     Scott Moore, NMSS
                     (301) 504-2514

1.  Training Topics for Moisture-Density Gauge Users
2.  List of Recently Issued NMSS Information Notices
3.  List of Recently Issued NRC Information Notices.

                                                           Attachment 1
                                                           IN 93-18
                                                           March 10, 1993
                                                           Page 1 of 1


      -   Radiological emergency response procedures for a damaged moisture- 
          density gauge

      -   Loss prevention, security, surveillance, and storage

      -   Physical inventory, accountability

      -   Notification of NRC regarding damaged devices and sources

      -   Proper disposal of gauges to the manufacturer (to avoid inadvertent
          transfer of a gauge to a scrap-metal broker and a possible foundry
          contamination incident)

      -   Completion of NRC Form 241, "Report of Proposed Activities in Non-
          Agreement States," when applicable

      -   Transportation requirements for shipping papers, labels, markings,
          certification of packaging, and blocking and bracing

      -   Radiation safety instruction for gauge users

      -   Portable-gauge accident scenarios, to avoid incidents and accidents
          with portable gauges

      -   Proper use of personnel-monitoring devices

      -   The terms and conditions of the license, and the occasions when it
          is appropriate to amend the license

      -   Other relevant requirements of 10 CFR Parts 19, 20, 
          and 30

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