Title: NORM
1NORM
HOW TO DEAL WITH THE NORM RADIATION
- MOHAMMED AL-KAABI
- Kerbala University- College of Science
- Physics Dep.
AHMAD UMER ABDULLAH Research and Development
2Why NORM Occurs
April 30, 2012
- Reservoir rock contains small amounts of natural
uranium and thorium and their radioactive
daughters. One daughter, radium, is water
soluble- dissolves in the reservoir
water. - Radium can precipitates with the barium and
calcium ions to make any scales slightly
radioactive (NORM). - Clay and fine particles can absorb the radium
from the formation water.
Kerbala University-Science College-Physics Dep.
www.uokerbala.edu.iq
3Why NORM Occurs
April 30, 2012
Kerbala University-Science College-Physics Dep.
www.uokerbala.edu.iq
4Hazards of NORM Scale
April 30, 2012
- Because NORM scale generally contains so little
activity, the external radiation field is
generally low. However some old tubular,
separators or pumps may give measurable radiation
fields. - Because of the high alpha content, NORM scale is
a significant internal hazard. - Therefore priority is to stop NORM scale
particles being inhaled or ingested. - This alpha toxicity also makes safe disposal
important.
Kerbala University-Science College-Physics Dep.
www.uokerbala.edu.iq
5Where it Appears
April 30, 2012
- NORM scale appears within the well fluid handling
system - Tubing string (especially tailpipe)
- Subsurface safety valves
- Wellheads
- Manifolds
- Separators
- Oil coolers
- Produced water pipework.
- It can also appear in the service water system,
in pig wax in storage cells etc.
Kerbala University-Science College-Physics Dep.
www.uokerbala.edu.iq
6Miscellaneous Valves
Kerbala University-Science College-Physics Dep.
www.uokerbala.edu.iq
7Pipework
Kerbala University-Science College-Physics Dep.
www.uokerbala.edu.iq
8Oil Cooler Plates
Kerbala University-Science College-Physics Dep.
www.uokerbala.edu.iq
9Oil Separators
Kerbala University-Science College-Physics Dep.
www.uokerbala.edu.iq
10How it Gets There
April 30, 2012
- Incompatible waters mix as they pass through
perforations - this starts scale depositing in
the tailpipe and tubing, then throughout the
plant. - Deposition is heaviest in areas of turbulence
beyond bends, valves, restrictions. - Also where temperature or pressure changes occur
such tubular, chokes, separators, coolers. - Separator deposits - clays may absorb
radionuclides directly from water.
Kerbala University-Science College-Physics Dep.
www.uokerbala.edu.iq
11What Scales Look Like
April 30, 2012
- Pure barium sulphate is hard dense white solid.
Pure NORM scale can be like that (especially in
tubular). - More usually thin, eggshell-like, light or dark
brown. - Can be stratified, like rings in a tree trunk.
- Separator sludge are granular suspensions.
- Sometimes deep in the surface matrix, so not
visible. - Pig waxes are black tarry materials, often with
chunks of rust and scale mixed in.
Kerbala University-Science College-Physics Dep.
www.uokerbala.edu.iq
12What Scales Look Like
April 30, 2012
Kerbala University-Science College-Physics Dep.
www.uokerbala.edu.iq
13NORM in Gas Wells
April 30, 2012
- NORM can also be found in gas wells where no
fluids are present. - Here it is due to radioactive lead-210 plating
out on surfaces from the gas. - The gas is radioactive because of the
radioactive radon gas in the formation
accumulating in it. - This radon then decays to the lead-210.
- This layer is thin and cannot always be seen.
Kerbala University-Science College-Physics Dep.
www.uokerbala.edu.iq
14Worker Protection
- Protection from External Exposure
- Protection from Internal Exposure
-
Kerbala University-Science College-Physics Dep.
www.uokerbala.edu.iq
15Protection from External Exposure Protection from
Internal Exposure
Kerbala University-Science College-Physics Dep.
www.uokerbala.edu.iq
16Protection from External Exposure
Three Effective Strategies-Time-
- Minimize the time , you will minimize the dose.
- Pre-plan the experiment/procedure to minimize
exposure time.
Kerbala University-Science College-Physics Dep.
www.uokerbala.edu.iq
17Three Effective Strategies-Distance-
Protection from External Exposure
- Doubling the distance from the NORM source can
reduce your exposure intensity by 25. - Use forceps, tongs, and trays to increase your
distance from the NORM source. - Move the item being worked on away from the
radiation area if possible. - Know the NORM intensity where you perform most
of your work, and move to lower dose areas during
work delays.
Kerbala University-Science College-Physics Dep.
www.uokerbala.edu.iq
18Three Effective Strategies -Shielding-
Protection from External Exposure
- Position shielding between yourself and the NORM
source at all permissible times. Take advantage
of permanent shielding (i.e. equipment or
existing structures). - Select appropriate shielding material during the
planning stages of the experiment. - Plexiglas, plywood and lead are effective in
shielding radiation exposure.
Exposure risk will increase when vessels are
opened for maintenance.
Kerbala University-Science College-Physics Dep.
www.uokerbala.edu.iq
19Protection from External Exposure
Plexiglas
Lead
Kerbala University-Science College-Physics Dep.
www.uokerbala.edu.iq
20Protection from internal Exposure
The Three Internal Exposure Pathways for a Worker
in the Petroleum Industry are
- Inhalation of NORM-contaminated dust or radon.
- Ingestion of NORM-contaminated particulates or
liquids. - Absorption of NORM-contaminated particulates or
liquids through the skin.
Kerbala University-Science College-Physics Dep.
www.uokerbala.edu.iq
21Protection from internal Exposure
The risks from maintenance activities include
- Improper safety procedures for entering pressure
vessels due to the build-up of radon gas. - Sanding, grinding or polishing activities on
equipment containing NORM scales that produce
airborne NORM particulates. - Handling of filters that are heavily
contaminated with radon progeny, without wearing
protective gloves.
Kerbala University-Science College-Physics Dep.
www.uokerbala.edu.iq
22Personal ProtectiveEquipment(PPE)
- Respiratory protection, including air purifying
respirators (half face, with goggles, or full
face), self-contained breathing apparatus (SCBA).
- Protective clothing, including coveralls
- gloves and footwear (i.e. CSA-approved
- safety boots, shoe covers, etc.)
Kerbala University-Science College-Physics Dep.
www.uokerbala.edu.iq
23Personal ProtectiveEquipment(PPE)
Kerbala University-Science College-Physics Dep.
www.uokerbala.edu.iq
24Personal ProtectiveEquipment(PPE)
- Radiation monitoring equipment, including a
radiation survey instrument, personal dosimeter
or alarming dosimeter.
- All PPE to be cleaned after job and monitored as
free from contamination. - Contaminated PPE should not be put into drums.
Kerbala University-Science College-Physics Dep.
www.uokerbala.edu.iq
25Radiation Badges
Personal ProtectiveEquipment(PPE)
- In any work associated with radiation that could
result in exposure above 10 of the limit, users
should wear a radiation badge. - Badges are designed to be worn to measure an
individuals exposure on a one or two-month
cycle. - If lead aprons are worn, badges should be clipped
to the shirt collar.
Kerbala University-Science College-Physics Dep.
www.uokerbala.edu.iq
26Use of NORM Warning Signs and Barricades
- Signs and barricades restrict access of
unauthorized workers or members of the public to
certain process areas.
Kerbala University-Science College-Physics Dep.
www.uokerbala.edu.iq
27Personal ProtectiveEquipment(PPE)
Pre-Use inspections for PPE
- Visual inspection of the integrity of the
equipment. - Pre-use review of maintenance records for
previously-used PPE, including confirmation of no
contamination, general maintenance schedules and
operational checks of proper PPE function, as
required.
Correct Use
NORM workers must received appropriate training
in the correct use of PPE, prior to its issuance.
Kerbala University-Science College-Physics Dep.
www.uokerbala.edu.iq
28Personal ProtectiveEquipment(PPE)
Post-Use inspections for PPE -prior to restocking
for future use -
- Conduct a visual check of equipment integrity .
- Conduct function tests of correct PPE operation,
as applicable. - Record results of function tests.
Kerbala University-Science College-Physics Dep.
www.uokerbala.edu.iq
29Thank you for your attention!
Kerbala University-Science College-Physics Dep.
www.uokerbala.edu.iq