Material plan for acquainting people who work in lab where metals are evaporated or sputtered:

Uranium and thorium

Friday, February 23, 2007 prepared by David Allred

 

These are the written Safety & Health Precautions Pertaining to Use of uranium/thorium sputter targets

Anyone who works in the lab shall be acquainted with the hazards associated with the metals they sputter in the lab

 

1)      For Uranium/thorium do the following activities.

 

2)      Read the following materials using the attached quiz to take notes.  

 

a)      From United Nuclear we read. “Alpha radiation is also emitted by Uranium metal, but this non-penetrating radiation is not a hazard unless the finely divided Uranium particles become airborne and are inhaled where the alpha radiation can damage sensitive lung tissue. Hence, it is important to ensure that concentrations remain below the OSHA standard of 0.25 mg/m3 of air.
     Uranium-238 metal is about as chemically toxic as other heavy metals such as lead.     Problems can best be avoided by careful control of any finely divided material and by good personal hygiene.”

http://www.unitednuclear.com/uraniummsds.htm

 

b)       Properties of Alpha particles:  They have a relatively large kinetic energy but due to the high (relatively) mass and charge they will not penetrate the epidermal layer of the skin.  Since keratinized epidermal cells do not have a nucleus and are relatively metabolically inert, they are basically immune to damage due to ionizing radiation.  Therefore the outer layer of skin is an effective shield for alpha particles (the one exception is the eye where viable metabolically active cells are at the surface).   The damage from alpha particles comes if they are injected, ingested or inhaled such that the alpha emissions interact directly with viable tissue.  If that occurs, alpha particles will cause approximately 20 times as much biological damage, per unit of energy absorbed, as gamma rays or beta particles.

 

c)      Read this to know about how radioactive things are. http://www.uic.com.au/ral.htm   and how much we get from Uranium.

 

d)      http://www.uic.com.au/nip17.htm  table on Some comparative radiation doses

 

e)      For more information  go to http://www.abelard.org/briefings/ionising-radiation.asp#depleted_uranium   you may wish to go to Aspects of depleted uranium munitions and read the sections  Depleted uranium (DU), Health hazards associated with Depleted Uranium, Radiological health hazards associated with Depleted Uranium, and Chemical health hazards associated with Depleted Uranium. 

 

f)        If more info is needed Google these 2 words: “uranium sievert” and look at the major three to five sites.

3)      List PPE to be used is gloves. 

4)      Do not use abrasives in system unless you are trained for Level 2 cleaning & follow those procedures.  Level 2 cleaning requires

 

5)       Sign and date: I have read, filled out the quiz, and discussed it and the material I have read.

a)      _____________________  signed                    date_______________

Printed Name

b)       Name/signature of person administering plan for person. _____________

 


 

Quiz.

1. Which of the following is not true for uranium metal?

1)      Alpha radiation is also emitted by Uranium metal, but this non-penetrating radiation is not a hazard unless finely divided Uranium particles become airborne and are inhaled where the alpha radiation can damage sensitive lung tissue.

2)      Uranium-238 metal is about as chemically toxic as other heavy metals such as lead

3)      Water fire extinguishers can be used on Uranium fires.

4)      All are true.

 

2. Which of the following is a “Route of Entry Health Hazard” associated with uranium

  1. Inhalation 
  2. Skin
  3. Ingestion
  4.  2 or more of the above.

3. T/F  Uranium metal can be handled BARE hands according to the OSHA standards, that is protective gloves are optional.

4. T/F  the Eye Protection: normal industrial safety for uranium is 0.25 mg/m3 of air.

 

5. If OSHA standards for uranium were 0.25 mg/m3 of air. Consider metal flakes (containing a uranium layer 100 nm thick) are suspended in 1000 cu ft of air. The flakes have a total surface area of  25 cm2, does this exceed OSHA standards?

 

6. T/F It is improper to wash off Uranium on skin etc. in the sink

7. When do special precautions have to be taken when cleaning after uranium?

  1. all cases
  2. all cases except for towels and gloves
  3. only if finely divided particles 

 

From Australian table on Radioactivity of some natural and other materials

 

8. Which is more radioactive 1 luminous Exit sign (1970s) 1 kg uranium?

 

9. T/F If the intrinsic radioactivity is the same, the radiation dose received by someone handling a kilogram of high grade uranium ore will be the same for exposure to a kilogram of separated uranium. 

 

10. T/F Depleted uranium is approximately 40 percent less radioactive than natural uranium

 

11.       DU is _____radioactive

 

Not       Mildly              Moderately  Strongly    Dangerously

 

12. T/F Depleted uranium does not significantly add to the background radiation that we encounter every day.  http://www.gulflink.osd.mil/faq_17apr.htm

13.  The PPE I will use are:

______________________________________________________


 

Bibliography and  Section 15: Regulatory Information

 

TSCA:  All components of this product are listed on the TSCA 8(b) inventory.  If identified components of this product are listed under the TSCA 12(b) Export Notification Rule, they will be listed below.

 

    TSCA 12(b) Component      Listed under TSCA Section

            None

 

SARA Title 3: Section 313 Information/Emissions Reporting (40 CFR 372):

 

    Component                  Reporting Threshold

    Uranium oxide

 

SARA-Section 311/312:  No components present in this product are subject to the reporting requirements of this statute.

 

Bibliography

 

  1. http://www.osha.gov/SLTC/healthguidelines/uraniuminsolublecompounds/index.html
  2. http://www.unitednuclear.com/uraniummsds.htm