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ES&H
Manual Radiation Control Supplement |
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Chapter 3 – Conduct of Radiological Work |
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Measures are taken to
maintain radiation exposure in controlled areas as low as is reasonably
achievable (ALARA) through facility and equipment design and administrative control. The primary methods used at Jefferson Lab are
physical design features (e.g., confinement of the beam to an underground
enclosure, prevention of access by interlock, ventilation control, remote handling,
and shielding) [§835.1001(a)].
Administrative controls and procedural requirements
are used only as supplemental methods to control radiation exposure. For specific activities where use of physical
design features is demonstrated to be impractical, administrative
controls and procedural requirements are used to maintain radiation exposures ALARA [§835.1001(b)].
In addition to normal safety and good housekeeping practices, when working with radiation producing equipment or radioactive material, personnel exposure can be minimized by:
310-01)
reducing the time spent in radiological areas - this can be done
by job planning, staging all necessary tools and equipment, etc.;
310-02)
maximizing the distance from the source of radiation
- the work site can be moved away from the source of radiation (if possible) or persons can keep as far from the source
as possible;
310-03)
maximizing the amount of shielding between workers and a radiation
source - if the work site cannot be moved, shielding may be used to reduce the
intensity of the radiation field; and
310-04)
minimizing the quantity of radioactive
material in systems, components and areas through careful selection of
materials, attention to operating conditions and good housekeeping.
311-01)
Technical requirements for the conduct of work, including
construction, modifications, operations, and maintenance and decommissioning,
shall incorporate radiological criteria to ensure safety and maintain radiation
exposures ALARA. To accomplish this, the design and planning
processes should incorporate radiological considerations in the early planning
stages. The checklist in Appendix 3A is helpful in
reducing occupational radiation exposure.
311-02)
At all times, the instructions
given by any Radiation Control Department (RCD) representative
or by this manual shall be followed.
Failure to do so may result in disciplinary actions including, but not
limited to: notation of infraction in the employee’s records, immediate
revocation of access authorization to radiological areas (not subject to grace
periods), suspension of source handling privileges, or dismissal. The final RCD recommendation shall be made by
the Radiation Control Department Manager (RCM). Action on any recommendation by the RCM is
the responsibility of the individual’s supervisor in consultation with the
Division Management and the Human Resources Department.
312
Planning for
Maintenance, Operations, and Modifications
312-01)
Maintenance and modification
plans and procedures shall be reviewed to identify and incorporate radiological
requirements, such as engineered controls and dose and
contamination reduction considerations.
Performance of this review is the responsibility of line management,
with support and concurrence from the RCD.
312-02)
Trigger levels requiring formal
radiological review of non-routine or complex work activities include:
a) Estimated dose greater than 250 mrem for an individual for the activity.
b)
Estimated collective dose greater than 1 person-rem for a work
evolution.
c)
Predicted collective dose from uptakes of airborne radioactivey in
excess of 100 mrem for a work evolution.
d)
General area removable contamination greater than 1000 times the
values in Appendix
2B.
e)
Activities involving individuals working in radiation fields above
1 rem/hour.
f)
Work involving significant potential for excessive radioactive
releases to the environment.
312-03)
For activities not exceeding the
thresholds in the above paragraph, performance of the review and documentation
of identified radiological requirements may be conducted as part of the
Radiological Work Permit process (see Article 321).
312-04)
Tasks with the potential to
exceed the trigger levels in Article 312-02 shall
undergo a formal, documented radiological review that is approved by the
Jefferson Lab Radiation Review Panel (JRRP).
They shall not exceed individual dose limits specified in Article 213. Among other considerations, this review shall
consider the following as appropriate:
a) Inclusion of Radiological Control Hold Points in the technical work documents.
b)
Elimination or reduction
of radioactivity through system or work area decontamination.
c)
Use of work processes
and special tooling to reduce time in the work area.
d)
Use of engineered
controls to minimize the spread of contamination and
generation of airborne radioactivity.
e)
Specification of special
radiological training or monitoring requirements.
f)
Use of mock-ups for high
exposure or complex tasks.
g)
Engineering, design, and
use of temporary
shielding to reduce radiation levels.
h)
Walkdown or dry-run of
the activity using applicable procedures.
i)
Staging and preparation
of necessary materials and special tools.
j)
Maximization of
prefabrication and shop work.
k)
Review of abnormal and
emergency procedures and plans.
l)
Identification of points
where signatures and second party or independent verifications are required.
m)
Establishment of success
or completion criteria, with contingency plans to anticipate difficulties.
n)
Development of a pre-job
estimate of collective exposure to be incurred for
the job.
o)
Provisions for waste minimization
and disposal.
p)
Identification of potential
environmental releases.
312-05)
Radiological
requirements identified as part of the above radiological review should be
documented in the job plans, procedures or work packages.
312-06)
Optimization techniques,
including cost-benefit analysis, represent a fundamental part of radiological
design analysis and work review. For
review of minor activities with low associated doses, a
cost-benefit evaluation is an intrinsic part of the engineering review process
and a detailed evaluation is not necessary.
For review and planning of major tasks involving higher collective dose
expenditures, a detailed and documented evaluation should be performed.
313
Infrequent or
First-Time Activities
313-01) With respect to routine, recurring process operations, special management attention should be directed to radiological activities that are infrequently conducted or represent first-time operations and could result in significant doses to workers. Planning for such activities should include:
a)
Formal radiological
review in accordance with Article 312-04.
b)
Senior management review
directed toward anticipation of concerns and emphasis on specification of
protective measures.
c)
Review and approval by
the JRRP.
d)
Enhanced line
management and RCD oversight during the initiation and conduct of the work.
e) The extent of the formal radiological review should be commensurate with the expected and potential hazards and required controls.
313-02) Radiography may be used to check, among other things, the integrity of welds on material at Jefferson Lab. Prior to commencement of radiographic operations, applicable procedures shall be reviewed. Radiography operations shall be conducted only under written authorization that has been reviewed by the RCD. The RCD shall be notified prior to the arrival of any radiography or other radioactive sources on site, and shall verify that required radiological controls are implemented, commensurate with exposure hazards and use of the source.
314-01)
Temporary shielding is
defined herein as shielding used for personnel protection from radiation that may be non-destructively disassembled or removed. Some examples are: water or lead shielding
around dumps; non-mortared cinder block walls; and movable shield walls or lead
baffles. This list is NOT all-inclusive.
314-02)
Installed temporary
shielding should be visibly marked or labeled with the
following or equivalent wording: “Radiation Control Department Shielding
Configuration – Notice: This configuration shall not be moved or altered in any
way without Radiation Control Department approval. For assistance call Radiation Control
Department at 876-1743.”
314-03)
Temporary shielding
visibly marked or labeled as in Article 314-02 shall not be disturbed without prior concurrence of the RCD. Disturbing such
shielding may result in excess radiation exposure to personnel, and may result in disciplinary action as described
in Article 311-02.
314-04)
The installation, use
and removal of temporary shielding shall be
controlled by policy and should be controlled by procedure when the work could
cause radiation levels that would result in the need
for a Radiation
Work Permit (RWP).
See Article 322.
314-05)
Prior to installation, the
effects of the additional weight of temporary shielding on systems and components should be evaluated and established to
be within the design basis.
314-06)
Installed temporary
shielding should be periodically inspected and surveyed to
verify effectiveness and integrity.
314-07)
Radiation surveys should
be performed during the alteration or removal of installed temporary
shielding.
314-08)
Installed temporary
shielding should be periodically evaluated to assess the
need for its removal or replacement with permanent shielding.
314-09) Site procedures may identify specific shielding applications, such as the shielding of low activity sources or samples that fall outside the recommendations of this Article.
315
Work Control Procedures/Documents
315-01)
Written
procedures shall be developed and implemented as necessary to ensure compliance
with 10 CFR 835, commensurate with the radiological hazards created by the
activity and consistent with the education, training and skills of the
individuals exposed to those hazards [§835.104].
315-02) Work control documents such as Temporary Operational Safety Procedures (TOSPs), Operational Safety Procedures (OSPs), RWPs, and Radiation Control Operating Procedures (RCOPs) (a special type of Standard Operating Procedure (SOP) required when the primary hazard is radiological) shall be used as necessary to support radiological control operations. These technical work documents reflect the relative level of hazard for the activity under consideration, define the prerequisites including equipment and training as necessary, and outline the steps necessary for safe work.
315-03)
Work control documents
used to control radiological work activities must be reviewed and approved by
the RCD.
315-04)
Radiological
Control Hold Points must be incorporated into work
control documents for steps that require action by the RCD to prevent radiation exposures in excess of Administrative Control Levels, high airborne
radioactivity concentrations, or the release of radioactivity to the environment.
316
Minimization of Internal
Exposure
Airborne
radioactivity control levels are discussed in Article
223. Estimates
of internal exposure shall be conducted in
accordance with Article
223 and should be minimized using the
following hierarchy of controls:
316-01)
Regarding the
control of airborne
radioactive material, and in any situation, to control
the inhalation of such material by workers to levels that are ALARA, confinement and ventilation should be used.
316-02) Under normal conditions, releases of radioactive material to the workplace atmosphere should be avoided. Wherever practicable, engineered controls, including containment of radioactive material at the source and ventilation, should be the primary methods of minimizing airborne radioactivity and internal exposure to workers. In any case, the internal exposure of workers to radioactive material should be maintained to levels that are ALARA.
316-03)
Administrative controls,
including access restrictions and the use of specific work practices designed
to minimize airborne contamination, should be used as secondary methods to
minimize internal exposure.
316-04)
When engineered and administrative
controls have been applied and the potential for exposure to airborne radioactivity still
exists, respiratory protection should be considered for use in limiting internal
exposures. Use of
respiratory protection should be considered under the following conditions:
a)
Entry into posted Airborne
Radioactivity Areas.
b)
During breach of
contaminated systems or components.
c)
Work in areas or on equipment
with removable contamination levels greater than 100 times the values in Appendix 2B.
316-05)
The selection of
respiratory protection equipment should include consideration of worker safety,
comfort, and efficiency. The use of
positive pressure respiratory
protection devices is recommended wherever practicable
to alleviate fatigue and increase comfort.
316-06) In specific situations, the use of respiratory protection may be contraindicated due to physical limitations or the potential for significantly increased external exposure. In such circumstances, specific evaluations shall be performed to determine expected exposure contributions from internal/external sources.
In every case, consideration
should be given to the effect of the use of respiratory devices (with respect to
decreased worker efficiency and safety) on the total dose
anticipated during an activity, and efforts should be made to keep the total dose ALARA.
The Radiological
Work Permit (RWP) is a work control document used to establish radiological controls to maintain ALARA for
intended work activities. The RWP informs workers of area radiological conditions and entry
requirements and provides a mechanism to relate worker exposure to specific work activities.
The RWP should include the following
information:
321-01)
Description of work
321-02)
Work area radiological
conditions
321-03)
Dosimetry requirements
321-04)
Pre-job briefing
requirements, as applicable
321-05)
Training requirements
for entry
321-06)
Personnel
protective equipment (PPE) requirements
321-07)
RCD coverage requirements
and stay time controls, as applicable
321-08)
Limiting radiological
conditions that may void the RWP
321-09)
Special dose or contamination reduction considerations
321-010)
Special personnel
monitoring considerations
321-011)
Technical
work document number, as applicable
321-012)
Unique identifying
number
321-013)
Date of issue and
expiration
321-014) Authorizing signatures
322
Use of Radiological
Work Permits
Written work authorizations (typically implemented through RWPs) shall be used for entry to and work within radiological areas. Dose tracking through a radiation work permit should be established whenever the area which will be occupied by the trunk of a worker’s body (usually 30 centimeters (1 foot) from the work piece) is greater than 25 mrem/hr, the total estimated dose to a worker exceeds 25 mrem in a work shift, or the work piece exceeds 250 mR/h on contact. Dose tracking may be employed at the discretion of the RCD at levels below these thresholds. RCD personnel should be vigilant for situations where extended periods of work are anticipated, and individual cumulative doses might exceed a significant fraction of a design goal during a dosimetry issuance period. Worker doses shall be evaluated each monitoring period for indications of such occurrences.
322-01)
RWPs shall be used to control the following
activities:
a)
Entry into High and Very
High Radiation Areas
b)
Entry into High
Contamination Areas and Contamination
Areas
c)
Handling of
materials with removable contamination that exceeds the values of Appendix 2B: Weighting
Factors For Organs And Tissues.
d) Any process identified by the RCD to need an RWP, such as first-time activities
322-02)
Job-specific RWPs shall be used to control non-routine operations or work in areas
with changing radiological conditions.
The job-specific RWP shall remain in effect
only for the duration of the job. If the
job is repetitive, a standing RWP may be used.
322-03)
General RWPs may be used to control minor radiological work activities, tours,
and inspections in areas with well-characterized and stable radiological
conditions. General RWPs should
not be approved for periods longer than 1 year.
322-04)
Radiological surveys
should be reviewed routinely to evaluate the adequacy of RWP requirements. RWPs shall be updated if radiological conditions change to the extent
that protective requirements need modification.
322-05)
RWPs should be posted at
the access point(s) to the applicable radiological work area, and shall be made available at the worksite.
322-06)
Workers shall affirm by
signature (including electronic signatures) that they have read, understand and
shall comply with the RWP prior to initial entry to
the area and after any revisions to the RWP.
322-07)
Worker pocket or electronic dosimeter readings
should be recorded in a format that identifies and provides linkage to the
applicable RWP.
323
Radiological Work Permit
Preparation
323-01)
The responsibility for ensuring
adequate planning and control of work activities resides with line
management. The lead work group
responsible for the planned activity or for the area should initiate the
preparation of the RWP.
323-02)
RWPs shall be reviewed
and approved by the RCD.
323-03)
The RWP should be based on current radiological surveys and anticipated
radiological conditions.
323-04)
The RWP shall be approved by the supervisor responsible for the work or
area and the appropriate Radiological Control supervisor (work-area supervisory
approval may be waived in the case of general or standing RWPs encompassing
multiple work areas and work groups).
Revisions or extensions to RWPs shall be
subject to the same approval process.
324-01)
At a minimum, pre-job
briefings shall be held prior to the conduct of work anticipated to exceed the
trigger levels identified in Article 312-02.
324-02)
At a minimum, the
pre-job briefing should include:
a)
Scope of work to be
performed
b)
Radiological conditions
of the workplace
c)
Procedural and RWP requirements
d)
Special radiological
control requirements
e)
Radiologically limiting
conditions, such as contamination or radiation levels that may void the RWP
f)
Radiological Control
Hold Points
g)
Communications and
coordination with other groups
h)
Provisions for
housekeeping and final cleanup
i)
Emergency response
provisions.
324-03)
Pre-job briefings should
be conducted by the cognizant work supervisor and a knowledgeable RCD representative.
324-04)
All persons utilizing an
RWP requiring a pre-job briefing shall be briefed
prior to using the RWP.
324-05)
A summary of
topics discussed and attendance at the pre-job briefing should be documented.
325
Personal
Protective Equipment (PPE) and Clothing
For the
purposes of this document, personal protective equipment (alternately, personnel protective equipment) consists of
clothing, respiratory protection equipment, portable containments, and other
such devices.
325-01)
Personnel shall wear protective
clothing during the following activities:
a)
Handling of materials or
entering areas with removable contamination in excess of Appendix 2B levels.
b)
As directed by
the RCD or as required by an RWP.
325-02) Protective equipment designated for radiological control should be:
a)
Marked in accordance
with Article
481.
b)
Used only for
radiological control purposes.
325-03)
PPE shall be
selected as prescribed by the controlling RWP. General guidelines for protective
clothing selection and use are provided in Appendix 3B and in Table 3-1.
Table 3-1: Guidelines for Selecting Protective Clothing
(PC)
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Removable Contamination Levels |
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Work
Activity |
Low (1
To 10 Times Appendix 2B
Values) |
Moderate (10
To 100 Times Appendix 2B
Values) |
High (>
100 Times Appendix 2B
Values) |
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Routine |
Full set of PC |
Full set of PC |
Full set of PC, double gloves, double shoe covers |
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Heavy work |
Full set of PC, work gloves |
Double set of PC, work gloves |
Double set of PC, work gloves |
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Work with pressurized or large volume liquids, closed system
breach |
Full set of non-permeable PC, face protection |
Double set of PC (outer set non-permeable), rubber boots, face
protection |
Double set of PC and non-permeable outer clothing, rubber boots,
face protection |
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Notes: 1. For hands-off tours or inspections
in areas with removable contamination levels 1 to 10 times the
values in Appendix
2B, combinations of lab
coats, shoe covers and gloves may be used instead of full PC. 2. In cases where the contaminated area is too small for the entire body to enter, or when working in glove boxes, fume hoods, or other devices with engineered protection, various partial protective clothing combinations may be used, and should be specified in work authorizing documents. |
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325-04)
The use of lab coats as
radiological protective clothing is appropriate for
limited applications such as those discussed in Appendix 3B where the potential for personal contamination is limited to the
hands, arms, and upper front portion of the body. Coveralls should be used as protective
clothing for performing physical work activities in Contamination Areas.
325-05)
Instructions for donning
and removing protective clothing should be posted at
the appropriate areas for routinely accessed Contamination Areas.
325-06)
The use of PPE or clothing for radiological controls beyond that authorized by
the RCD may detract from work performance and is
contrary to ALARA
principles and waste minimization practices.
Such use should be avoided.
Personnel entry control shall be maintained for each radiological area. The degree of personnel entry control shall be commensurate with existing and potential radiological hazards within the area.
The RCD incorporates entry and exit requirements into work control documents, Radiological Work Permits (RWPs) and Radiological Control Operating Procedures (RCOPs), to ensure that entry control requirements are met. These and other administrative procedures include actions essential to ensure the effectiveness and operability of interlocks, barricades, devices, alarms, locks, and other devices used to control entry and exit at radiological areas.
Under no circumstance
shall control(s) be installed at any radiological area exit that would prevent rapid
evacuation of personnel under emergency conditions [§835.501(e), §835.502(d)].
NOTE: The requirements in subparts F (Entry Control
Program) and G (Posting and Labeling) of 10 CFR 835 do not apply to radioactive
material transportation by DOE or a DOE contractor if conducted:
·
Under the continuous
observation and control of an individual who is knowledgeable of and implements
required exposure control measures, or
· In accordance with Department of Transportation regulations or DOE orders that govern such movements.
Entry controls in this section apply to accessible areas. As defined in Article 238, Exclusion Areas are not accessible areas. Beam enclosure areas that are configured with a certified Personnel Safety System are exclusion areas when the beam or RF power is operable.
Successful completion of General Employee Radiological Training or the equivalent as approved by the RCD is required for unescorted entry into Controlled Areas. Untrained visitors must be escorted at all times while in Controlled Areas. Visitors shall not enter into radiological areas without the express permission of the RCD.
Due to the small number and size of Contamination Areas normally present at Jefferson Lab, Radiological Buffer Areas (RBA) are not typically employed. To a significant degree, the Radiologically Controlled Area (RCA) designation used at Jefferson Lab serves the same purpose as the RBA. Radiological Buffer Areas should be considered for use around readily accessible contamination and high contamination areas that persist for long periods (more than a few weeks) and have reasonably large total surface areas (e.g. 100 square feet). Establishing RBAs for small or infrequently entered contamination areas may not be consistent with the ALARA process.
When implemented, the following guidance applies to RBAs.
332-01)
Minimum requirements for
unescorted entry into Radiological Buffer Areas
shall include the following:
a)
Radiological Worker I training.
b) Personnel dosimetry, as defined by governing work control documents
332-02)
Personnel who exit a Radiological Buffer Area containing Contamination Areas, High Contamination Areas, or Airborne Radioactivity Areas
should monitor themselves as specified in Article 338.
333
Radioactive
Material Areas
General Employee Radiological
Training is required for unescorted entry into Radioactive Material Areas. Other requirements may
apply depending on the use and quantity of the radioactive material and the equivalent dose rate in the area. These requirements will be contained in the
applicable postings for the area.
334
Entry into Radiologically
Controlled Areas
Radiologically
Controlled Areas (RCAs) are areas where radiological
controls are implemented. Routine
occupancy in RCAs may result in a dose greater than 100 mrem per year to an individual. Unescorted access to an
RCA normally requires Radiological Worker-I training and a properly worn
personal dosimeter (OSL badge). RCAs may or may not contain Radiological Areas.
334-01)
A “radiological area” is defined as a Radiation Area, High
Radiation Area, Very High Radiation Area, Contamination Area, High
Contamination Area, or an Airborne Radioactivity
Area. Personnel entry
control shall be maintained for each radiological area [§835.501(a)]. The degree of personnel entry control shall
be commensurate with existing and potential radiological hazards
within the area [§835.501(b)]. One or more of the following methods shall be
used to ensure personnel entry control:
a) Signs and barricades;
b)
Control devices on
entrances;
c)
Conspicuous visual
and/or audible alarms;
d)
Locked entrance ways; or
e)
Administrative controls [§835.501(c)].
334-02) Written authorizations, such as RWPs, shall be required to control entry into and perform work within radiological areas. These authorizations shall specify radiation protection measures commensurate with the existing and potential hazards [§835.501(d)].
334-03)
Minimum requirements for
unescorted entry into Radiation Areas shall include
the following:
a)
Satisfactory completing
of Radiological Worker I training
b)
Worker's signature on
the RWP, as applicable
c) Properly worn personnel dosimetry.
334-04)
Minimum requirements for
entry into High Radiation Areas shall include the
following:
a)
The area shall be
monitored as necessary during access to determine the exposure rates to which the individuals are exposed [§835.501(a)(1)]; and
b)
Satisfactory completing
of Radiological Worker I Training,
c)
Worker's signature on
the RWP,
d)
Properly worn
personnel dosimeter, and
e) Supplemental dosimeter or other means capable of providing an immediate estimate of the individual’s integrated equivalent dose to the whole body during the entry [§835.502(a)(2)].
334-05)
Physical controls to prevent inadvertent
or unauthorized access to High and Very High Radiation Areas shall be
maintained in accordance with 10
CFR 835.502 at each entrance or access point to
a high radiation area where radiation levels exist such that an individual
could exceed an equivalent dose to the whole body of 1 rem in any one hour at
30 centimeters from the source or from any surface that the radiation
penetrates [§835.502(b)].
334-06) In addition to the physical controls specified above, the minimum requirements for entry into High Radiation Areas where it is likely that a worker’s whole body will be exposed to a dose rate exceeding 1 rem/h shall include:
a)
A determination of the
worker’s current exposure, based on primary and
supplemental dosimeter readings
b)
Pre-job briefing, as
applicable
c)
Review and
determination by the RCD regarding the required
level of Radiological Control Technologist coverage
d) Consideration of the items described in Articles 312 and 313.
334-07)
Prior to the first entry
into any area where a source could create a Very High Radiation Area, a survey shall be made after the source has been secured or
shielded to verify the very high radiation field has
been terminated [§835.502(c)]. For accelerator enclosure entry after shutdown,
a radiation survey begins upon entry to locate radiological
areas. This survey
also serves as an indicator that the accelerator is shut down and prompt radiation producing operations have terminated. In some cases, such as when access is
restricted to an area where activation of accelerator components is negligible,
alarming fixed instrumentation or personnel electronic alarming pocket dosimeters may be used to indicate that prompt radiation production has terminated.
334-08)
The Crew
Chief and the RCD should be notified prior to
personnel entry to areas where operational or system changes made by operations
personnel could result in significantly increased area dose rates.
334-09)
The number, issue, and
use of keys shall be strictly controlled where locked entryways are used to
control access to High and Very High
Radiation Areas. The
loss of any key for these areas shall be immediately addressed by the RCD
[§835.502(c)].
334-010)
Inspections of
the physical access controls to accessible High and Very
High Radiation Areas shall be made at appropriate intervals
to verify controls are adequate to prevent unauthorized entry [§835.502(c)].
335
Contamination and Airborne
Radioactivity Areas
335-01)
Minimum requirements for
entry into Contamination Areas shall include the
following:
a)
Radiological Worker II
training
b)
Worker’s signature on
the RWP, as applicable
c)
Protective clothing
d)
Personnel dosimetry, as
appropriate.
335-02)
Work in High
Contamination or Airborne Radioactivity Areas, when the airborne
activity is due to particulate radioactivity should also
include the following:
a)
An evaluation of the need for respiratory protection equipment
b) Pre-job briefings
335-03)
Personnel exiting Contamination,
High Contamination, or Airborne Radioactivity Areas
(for particulate activity) shall use appropriate monitoring to detect and prevent the spread of contamination [§835.1102(d)]. The
following shall be performed by individuals exiting radiological areas established to control removable contamination and/or airborne
radioactivity as appropriate:
a)
Remove protective
clothing as specified in Appendix 3B
b)
Monitor to detect
personnel contamination in accordance with Article
338
c)
Tools or equipment being
removed from the area are subject to the same monitoring requirements, and if
applicable, shall be monitored for release in accordance with Article
421.
335-04)
Exit points from Contamination, High Contamination, or Airborne Radioactivity Areas should include the following, taking into account the size,
configuration and duration of existence of the area:
a)
Step-off pad located
outside the exit point, contiguous with the area boundary
b)
Step-off pads maintained
free of radioactive contamination
c)
Labeled containers
inside the area boundary for the collection of protective clothing and equipment
d)
Contamination monitoring equipment located as close to the step-off pad as background radiation levels permit.
335-05)
Multiple step-off pads
should be used at the exits from High Contamination Areas. Use of multiple step-off
pads is described in Appendix 3B.
335-06) Protective clothing and monitoring requirements specific to benchtop work, laboratory fume hoods, sample stations and gloveboxes are identified in Article 347.
336
Visitor Entry Restrictions
336-01)
Signs and training
identify area entry requirements and access restrictions for visitors.
336-02)
Visitors with a
demonstrated need to enter the following areas may be allowed access if such
access is controlled with a combination of training and the use of escorts
trained for the specific area:
a)
Radiation Areas
b)
Radioactive Material Areas
336-03)
Visitors shall be
prevented from entering High Radiation Areas and Very
High Radiation Areas and shall be prohibited access to Contamination, High Contamination, and Airborne
Radioactivity Areas.
336-04) Training requirements for visitors are identified in Article 622.
337
Controlling the Spread of Contamination
The following measures should be used to prevent the spread of contamination from Contamination Areas and Airborne Radioactivity Areas:
337-01)
Use solid barriers to
enclose areas wherever practicable
337-02)
Mark and secure items
such as hoses and cords that cross the boundary
337-03)
Control and direct
airflow from areas of lesser to greater removable contamination
337-04) Use engineered controls and containment devices such as glove bags, gloveboxes, tents, and high efficiency particulate air filtering system (HEPA)–filtered ventilation.
338
Monitoring for Personnel Contamination
Jefferson Lab
shall use appropriate monitoring to detect and
prevent the spread of contamination. Monitoring shall be performed by individuals exiting radiological
areas established to control removable contamination and/or
particulate airborne radioactivity.
338-01)
Personnel shall perform
a whole body survey under the following conditions:
a)
Immediately upon exiting
Contamination, High Contamination, and Airborne
Radioactivity Areas (where established for particulate
airborne radioactivity)
b)
As directed by the RWP or the RCD
338-02)
In addition to the
above, personnel exiting a Radiological Buffer Area containing Contamination, High Contamination or Airborne
Radioactivity Areas should, at a minimum, perform a hand
and foot frisk. This frisk is optional
if the Radiological Buffer Area exit is immediately adjacent to the location
where the exiting individual has already performed a whole body survey.
338-03)
Where monitoring cannot be performed at the exit from Contamination, High Contamination, or Airborne Radioactivity Areas due to high background radiation
levels, personnel shall:
a)
Remove all protective
equipment and clothing at the exit
b)
Proceed directly to the
nearest designated monitoring station
c)
Conduct a whole body
survey.
338-04)
Personnel monitoring shall
be performed after removal of protective clothing
and prior to washing or showering.
338-05)
Personnel monitoring
shall be performed using instruments that meet the minimum detection requirements of Article
221-02.
Guidelines for personnel frisking are provided in Appendix 3C.
338-06)
Personal items, such as
notebooks, papers and flashlights, shall be subject to the same monitoring requirements as the person carrying them.
338-07) Instructions for personnel monitoring should be posted adjacent to personnel monitoring instruments or monitors.
Authorization is required to perform work within radiological
areas. This
authorization is contained in Radiological Work Permits (RWPs) and other work control documents that
include specific radiation protection measures.
341-01)
Radiological work
activities shall be conducted as specified by the RWP and other work control documents.
341-02) Prerequisite conditions, such as tag-outs and system isolation, shall be verified in accordance with the work control documents before work is initiated.
342
Work Conduct and Practices
342-01)
Contamination levels
caused by ongoing work shall be monitored and should be maintained ALARA.
Work should be curtailed and decontamination performed at pre-established
levels, taking into account worker exposure.
342-02)
Tools and equipment
should be inspected to verify operability before being brought into Contamination, High Contamination, or Airborne Radioactivity Areas.
342-03)
The use of
radiologically clean tools or equipment in Contamination, High Contamination, or Airborne Radioactivity Areas should be minimized (e.g., by the implementation of a
contaminated tool crib). When such use
is necessary, tools or equipment with complex or inaccessible areas should be
wrapped or sleeved to minimize contamination.
342-04)
Engineered controls,
such as containment devices, portable or auxiliary ventilation and temporary
shielding, should be installed in accordance with the technical work
documents and inspected prior to use.
342-05)
Hoses and cables entering
the work area should be secured to prevent the spread of contamination or
safety hazards.
342-06)
The identity of
components and systems should be verified prior to work.
342-07)
Work activities and
shift changes should be scheduled to prevent idle time in radiological
areas.
342-08)
Where practicable, parts
and components should be removed to areas with low dose rates to perform work.
342-09)
Upon identification of
radiological concerns, such as inappropriate work controls or procedural
deficiencies, workers shall immediately report the concern to line supervision
or the RCD.
342-010)
Requirements for area
cleanup should be included in the work control documents. Work activities should
not be considered complete until support material and equipment have been
removed and the area has been returned to at least pre-work status.
342-011) To minimize intakes of radioactive material by personnel, smoking, eating, or chewing should not be
permitted in Radiation Areas, High Radiation
Areas, Contamination Areas, High
Contamination Areas, potentially contaminated areas,
Airborne Radioactivity Areas, or Radioactive
Material Areas.
343-01)
Radiological Control
personnel shall document abnormal radiological situations, and should maintain
logs on work controlled by work control documents such
as RWPs, which include the status of work activities
and other relevant information.
343-02)
During continuous or
extended daily operations, oncoming RCD personnel should review logs and
receive a turnover briefing from the personnel they are relieving.
343-03)
Communication systems
required by the RWP or work control document should be checked for operability before being brought into the
work area and periodically during work.
343-04)
Workers shall keep RCD
personnel informed of the status of work activities that affect radiological
conditions.
344
Review of Work
in Progress
344-01)
As part of their normal
work review, radiological control and work supervisors should periodically
review ongoing jobs to ensure prescribed radiological controls are being
implemented.
344-02)
RCD personnel should
conduct frequent tours and inspections of the workplace to review the adequacy
of radiological work practices, posting and area
controls.
344-03)
During the
performance of jobs for which a pre-job dose
estimate was made, the RCD, in cooperation with line
management, should periodically monitor collective dose accumulation and compare it with the pre-job dose estimate. Differences
should be reviewed to identify causes and assess the need for corrective
actions.
345
Stop Radiological
Work Authority
345-01)
Radiological Control
Technologists (RCT) and their supervisors, line supervision, and any worker
through their supervisor, has the authority and responsibility to stop radiological
work activities for any of the following reasons:
a)
Inadequate radiological
controls,
b)
Radiological controls
not being implemented, or
c)
Radiological Control Hold Point not being satisfied.
345-02)
Stop radiological
work authority shall be exercised in a justifiable and
responsible manner (e.g., barring access to the area, revoking the RWP, or revoking individual training).
345-03)
Once radiological
work has been stopped, it shall not be resumed until proper
radiological control has been reestablished.
345-04)
Resumption of radiological
work requires the approval of the line manager responsible
for the work and the RCM or designee.
346
Response to
Abnormal Situations
346-01)
An emergency in which there is a real or potential exposure to radiation or release of radioactive
material in excess of applicable administrative control
levels or limits is considered to be a radiation emergency. A radiation emergency can occur as a result of accelerator operations or as a result of
the use or handling of radioactive material, or
radioactive sources.
346-02)
In the event of a
radiation emergency that results from accelerator operations, the Crew Chief
shall be notified at the Machine Control Center, ext. 7047 or ext. 7050. The Crew Chief shall then notify the
appropriate personnel as indicated in the Jefferson Lab ES&H Manual (including the RCD) using the
following information.
RCD Notification Information (as of May 2010), current information may be found at http://www.jlab.org/accel/RadCon/personnel.html.
|
Name |
Mail
Stop |
Phone |
Cell
Phone |
|
Vashek Vylet (RCM) |
MS 6B |
ext. 7551 |
757-218-2733 |
|
Keith Welch |
MS 6B |
ext. 7212 |
757-876-5342 |
|
24 Hour Cell Phone757-876-1743 In the event
of a radiation emergency, the RCD, as listed above, shall be notified. |
|||
346-03)
Response to increasing
or unanticipated radiation levels, as identified by
a supplemental dosimeter or Area Radiation Monitor
Alarm, should include the following actions:
a)
Stop work activities,
b)
Alert others,
c)
All personnel
immediately exit the area, and
d)
Notify the RCD.
346-04)
Response to personnel
contamination should include the following actions:
a)
Remain in the immediate
area,
b)
Notify RCD personnel,
and
c)
Take actions that may be
available to minimize cross-contamination, such as putting a glove on a
contaminated hand.
346-05)
Response to a spill of radioactive
material should include the following actions:
a)
Stop or secure the
operation causing the spill,
b)
Warn others in the area,
c)
Isolate the spill area
if possible,
d)
Minimize individual exposure and contamination,
e)
Secure unfiltered
ventilation, and
f) Notify RCD personnel.
g) For spills involving highly toxic chemicals, workers should immediately exit the area without attempting to stop or secure the spill. They should then promptly notify the Lab Chemical Assistance Team and RCD personnel by calling the guard at x4444, then calling x7863.
347-01)
Control of material and
equipment
a)
Except as provided in
paragraphs (b) and (c) of this section, material and equipment in Contamination
Areas, High Contamination Areas,
and Airborne Radioactivity Areas shall not be
released to an area outside of a Contamination Area,
High Contamination Area, or Airborne
Radioactivity Area if:
1)
Removable surface
contamination levels on accessible surfaces exceed the removable surface
contamination values specified in Appendix
2B; or
2)
Process knowledge suggests
that the removable surface contamination levels on inaccessible surfaces are
likely to exceed the removable surface contamination values specified in Appendix 2B
[§835.1101(a)].
b)
Material and equipment
exceeding the removable surface contamination values specified in Appendix 2B may be conditionally released for movement on-site from one radiological
area for immediate placement in another radiological
area only if appropriate monitoring is performed and appropriate
controls for the movement are established and exercised [§835.1101(b)].
c)
Material and equipment
with fixed contamination levels that exceed the total surface contamination
values specified in Appendix 2B may be released for use in Controlled
Areas outside of radiological
areas only under the following conditions:
1)
Removable surface
contamination levels are below the removable surface contamination values
specified in Appendix 2B; and
2)
The material or equipment is
routinely monitored and clearly marked or labeled to alert personnel of the
contaminated status [§835.1101(c)].
347-02) Control of areas
a)
Appropriate controls
shall be maintained and verified which prevent the inadvertent transfer of
removable contamination to locations outside of radiological areas under normal operating conditions [§835.1102(a)].
b)
Any area in which
contamination levels exceed the values specified in Appendix 2B shall be controlled in a manner commensurate with the physical
and chemical characteristics of the contaminant, the radionuclides present, and
the fixed and removable surface contamination levels [§835.1102(b)]
c)
Areas accessible to
individuals where the measured total surface contamination levels exceed, but
the removable surface contamination levels are less than, corresponding surface
contamination values specified in Appendix
2B shall be controlled as follows when
located outside of radiological areas:
1)
The area shall be routinely monitored
to ensure the removable surface contamination level remains below the removable
surface contamination values specified in Appendix 2B; and
2)
The area shall be conspicuously
marked to warn individuals of the contaminated status [§835.1102(c)].
d) Individuals exiting contamination, high contamination, or airborne radioactivity areas shall be monitored, as appropriate, for the presence of surface contamination [§835.1102(d)].
e)
Protective
clothing shall be required for entry to areas in which
removable contamination exists at levels exceeding the removable surface
contamination values specified in Appendix 2B [§835.1102(e)].
348
Controls for
Benchtop Work, Laboratory Fume Hoods, Sample Stations and Gloveboxes
The following
requirements are applicable to radiological work in
localized benchtop areas, laboratory fume hoods, sample stations and glovebox operations
located in areas that are otherwise contamination free when contamination
levels associated with the operations exceed or are likely to exceed Appendix 2B values. These practices
are also applicable to work in isolated areas or components whose physical
configuration creates a similar work environment, such as the interior of a
target chamber having locally contaminated targets.
348-01)
An RWP shall be issued to control radiological work in localized benchtop areas, laboratory fume hoods, sample
sinks, and gloveboxes.
348-02)
The following controls
apply to localized bench top and laboratory fume hood operations (these
controls apply to laboratory bench-top sample preparation/analysis when the
expected total activity in the sample(s) is high enough to produce an area
exceeding Appendix 2B values in the event of a spill):
a)
Protective clothing
shall, at a minimum, include lab coats and gloves. Gloves should be secured at the wrist as
necessary.
b)
Shoe covers should be
considered based on the potential for floor contamination.
c)
Workers should
periodically monitor their hands during work.
d)
Upon completion of work
or prior to leaving the area, workers shall monitor those areas of their body
that are potentially contaminated. At a
minimum, this includes hands, arms, and front portions of the body. Workers should perform a whole body survey.
e)
Install temporary
shielding as appropriate.
f)
When finished with
operations, decontaminate and remove equipment.
348-03)
The following controls
apply to sample station operations:
a)
Protective clothing
shall, at a minimum, include gloves.
Gloves should be secured at the wrist as necessary.
b)
Shoe covers should be
considered based on the potential for floor contamination.
c)
If there is a potential
for splashing or airborne radioactivity, such as when taking pressurized
samples, additional controls such as rubber aprons, face shields, full protective
clothing (PCs), or respiratory protection should be
instituted.
d)
Workers should
periodically monitor their hands during work.
e)
Upon completion of work
or prior to leaving the area, workers shall monitor those areas of their body
that are potentially contaminated. At a
minimum, this includes hands, arms, and front portions of the body. Workers should perform a whole body survey.
348-04)
The following controls
apply to glovebox operations:
a)
Gloveboxes should be
inspected for integrity and operability prior to use.
b)
Gloveboxes should be
marked with, or survey measurements should be posted to identify, whole body
and extremity dose rates, as appropriate.
c)
Gloves in addition to
those integral to the glove box should be worn when contamination levels in the
glove box may exceed 100 times Appendix
2B values.
d)
Shoe covers should be
considered based on the potential for floor contamination.
e)
Workers should
periodically monitor their hands during work.
f)
Upon completion of work or prior
to leaving the area, workers shall monitor those areas of their body that are
potentially contaminated. At a minimum,
this includes hands, arms, and feet.
Workers should perform a whole body survey.
349
Controls for Hot
Particles
Hot particles
are small, discrete, highly radioactive particles capable of causing extremely
high doses to a localized area in a short period of
time. Hot particle contamination may be present
or be generated when contaminated systems are opened or when operations such as
machining, cutting, or grinding are performed on highly radioactive
materials.
349-01)
A hot particle is
defined at Jefferson Lab as a small radioactive particle, possibly not visible
to the eye, having an emission rate of at least 10,000 disintegrations per
second total beta-gamma activity.
349-02)
Measures for controlling
hot particles, as identified in items 03 through 07 of this Article, should be
implemented under the following conditions:
a)
Upon identification of
hot particles,
b)
During new or
non-routine operations with a high potential for hot particles, based on
previous history, or
c)
Upon direction of the RCD.
349-03)
When practicable,
the use of containment tents, glove boxes, or other engineered methods should
be applied to control of hot particles, as applicable.
349-04) Areas or operations with the potential for hot particle contamination should be surveyed in accordance with Article 553.
349-05)
Contamination Area
postings should be annotated to specifically identify the presence of hot
particles.
349-06)
Access to hot particle
areas should be controlled by a job-specific RWP. The following controls should be considered
for inclusion on the RWP:
a)
Periodic
personnel monitoring during the work activity, at a frequency based on the
potential magnitude of personnel exposure,
b) Periodic surveys at boundaries and areas surrounding the hot particle area, at increased frequency during periods of work,
c)
Additional PPE and clothing,
d)
Direct RCD coverage
during work and/or assistance during protective clothing removal, and
e)
Use of sticky pads or multiple
step-off pads.
349-07) PPE and clothing used in hot particle areas should be segregated from other radiological protective equipment and clothing during laundering and surveyed prior to reuse.
349-08)
Response to hot particle
skin contamination of personnel should include the following:
a)
Immediate removal and retention
of the hot particle for subsequent analysis,
b)
Analysis of the
particle,
c)
Assessment of worker dose, and
d)
Evaluation of work control
adequacy.
During
the conduct of radiological work and the handling of radioactive materials,
abnormal events may occur that could indicate a weakness or area of
programmatic breakdown of radiological controls. Prompt, consistent gathering of facts related
to such events is required to satisfy reporting and investigation requirements
and to formulate corrective actions to prevent recurrence. In addition, successful performance or
completion of unique activities should be evaluated to identify and incorporate
appropriate lessons learned.
Analysis
of the facts should reveal areas where improvements can be made or identify
methods to prevent the recurrence of undesired results.
Critiques
are meetings of the personnel knowledgeable about an event (either a success or
an abnormal event) to document a chronological listing of the facts. The purpose of the critique is not to assign blame, but to establish and record the
facts and develop lessons learned.
351-01)
Critiques should be conducted for successes and abnormal events.
351-02)
Critique leaders should be trained in the required elements of the critique process and the appropriate methods of conducting and
controlling the critique.
351-03)
Critique meetings should be conducted as soon as practicable after
the event or situation is stabilized, or after a successful evolution is
completed. Critiques of abnormal events should be conducted preferably before
involved personnel leave for the day.
351-04)
Critiques and investigations of unusual events should be conducted
in accordance with Jefferson Lab ES&H Manual Chapter 5200
Event Investigation and Causal Analysis Process.
352-01) Performance should be reviewed after completion of non-routine radiological work.
352-02) As appropriate to the work in question, post-job reviews should include reviews of:
a)
Total
and individual doses compared to pre-job estimates
b)
Efficacy
of the radiological controls implemented for the work
c)
Any
adverse events occurring during the work
d)
Conflicts
between radiological safety requirements and other safety requirements
e)
Opportunities
to improve performance or efficiency during repeated or similar work
f)
Significant
differences between expected and actual radiological conditions or other issues
affecting the work
g)
Worker
input regarding possible improvements in radiological safety practices for
repeated or similar work.
Lessons learned are available from post-job reviews and reports of
past radiological events on site and at other facilities. See the Lessons
Learned Program for details of the laboratory’s program. The RCD, in conjunction with line management, should evaluate
lessons learned, provide prompt distribution, and incorporate the lessons into
the radiological control program, the radiological training program, and
related operations. To ensure wide
distribution to Jefferson Lab personnel, lessons learned should be submitted on
a Notable Event Report. Training for RCTs and other RCD staff should
include lessons learned from Jefferson Lab and other facilities with similar
radiological concerns. Jefferson Lab RCD
personnel should periodically meet with other radiological professionals from
other DOE accelerators to discuss lessons learned.
|
|
|
Part 6
Considerations for the Design and
Control of Facilities |
|
|
Measures shall be taken to maintain
ALARA radiation exposure
in Controlled Areas through facility and equipment
design and administrative control. The primary methods used shall be physical design
features (e.g., confinement, ventilation, remote handling, and shielding). Administrative controls and procedural requirements shall be employed only as
supplemental methods to control radiation exposure
[§835.1001].
361-01) During the design of new facilities or modification of existing facilities, the following objectives shall be adopted:
a)
Optimization methods
shall be used to assure that occupational exposure
is maintained ALARA in developing and justifying
facility design and physical controls [§835.1002(a)].
b)
The design objective for
controlling personnel exposure to a radiological
worker from external sources of radiation in areas of continuous occupational occupancy (2000 hours per
year) shall be to maintain exposure levels below an
average of 0.5 mrem (5 mSv) per hour and as far below this average
as is reasonably achievable. The
Jefferson Lab design goal for a radiologically controlled area is such that a radiological
worker will not receive a dose in excess of 250 mrem in a year [§835.1002(b)].
c)
The design objectives
for exposure rates for potential exposure to a radiological worker where
occupancy differs from the above shall be ALARA and
shall not exceed 20% of the applicable standards in 10
CFR 835.202 [§835.1002(b)].
361-02)
For specific activities
where use of physical design features is demonstrated to be impractical, administrative
controls and procedural requirements shall be used to
maintain radiation exposures ALARA [§835.1001(b)].
361-03)
The design objective for
control of airborne radioactive material shall be to
avoid releases to the workplace atmosphere.
In the event that is not feasible, exposure
to workers shall be kept ALARA through use of
ventilation and confinement [§835.1002(c)].
361-04) The design or modification of a facility and the selection of materials shall include features that facilitate operations, maintenance, decontamination, and decommissioning [§835.1002(d)].
362
Control Considerations and Procedures
362-01)
The ALARA process will be utilized for personnel exposures to ionizing
radiation [§835.1003(b)].
362-02)
Other performance goals
and indicators appropriate to design and control procedures should be monitored, such as:
a)
PPE requirements and
practices to accommodate other hazards on the site
(i.e., non-essential radiation protective equipment
that potentially worsens a coincident hazard).
b)
Use of respiratory
protection as normal conduct of operation due to lack of engineered controls
and temporary nature of the work.
c)
Monitoring and survey
frequency for inactive facilities or large areas that are infrequently occupied.
Inclement
weather or other environmental conditions may disrupt radiological
controls. If that occurs, the following
actions should be considered:
363-01)
The use of covers, wind screens
and runoff collection basins to preclude the inadvertent spread of radioactive
material.
363-02)
Provisions for worksite
personnel to assemble and be monitored prior to release or reestablishment of
work.
363-03)
Evaluation of
work area to determine if a need exists for modified work controls or
decontamination.
364
Other Workplace Hazards
Radiological
controls should be implemented in a balanced way to ensure that protection from
all workplace hazards can be implemented. Other hazards to
consider include, but are not limited to:
·
General construction hazards
·
Flammable materials
·
Reactive chemicals
·
Heat stress
·
Chemical exposures
·
Energized electrical
equipment
·
Biological hazards
·
Rotating equipment
·
Noise and vibration
·
Restricted vision with
respirator use
·
Increased stay times
due to PPE
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|
ISSUING
AUTHORITY |
CHAPTER
AUTHOR |
APPROVAL
DATE |
EFFECTIVE
DATE |
EXPIRATION
DATE |
REV. |
|
|
|
|
RadCon Dept |
07/01/10 |
07/01/10 |
07/01/13 |
4 |
|