DOT Regs and "Contamination"

[scooter]

October 1, 2004 is just around the corner.  ???49 Part 171, 172, 173, et al is upon us. "Contamination" is defined now as 0.4 Bq/cm2 for beta and gamma emitters.  That is ~2400 dpm/100cm2.  I take this to mean that DOE 5400.5 release criteria of 5000 dpm/110 cm2 is basically being replaced.  How are you all going to meeting the pancake probe scan of <or= 2400 dpm/100cm2?  The problem could occur if you release material per 5400.5 at say 3500 dpm/100cm2, have a vehicle accident and when the survey is performed at the scence low and behold it violates DOT Regs.  I am asking for how others are working this.  I heard folks are quoting 100 cpm = 1000 dpm, that may be correct, but I do not understand 100 cpm = 1000 dpm (PER 100cm2).  I that this was always 5000 dpm/100cm2 in the INPO days.  Any help would greatly be appreciated.  Thank you ahead of time!

[alphadude]

The accident scenario that you mention is confusing. The limits are based on "no accidents". We plan for safe shippments.

If an accident occurs the shippment is out of compliance.  What is the basic question that you want answered??

[Fast Fission]

I don't quite understand the question either. But the 49CFR limits are DOT and have no effect on the DOE limits, they don't in any way supersed or change the DOE limits. EXCEPT, when making a radioactive material shipment across public roads the DOT limits apply.

But if something was released under DOE limits (5000 dpm/ 100 cm2) as non radioactive and was subsequently shipped under DOT regulations, the DOT contamination limit would not be applicable because it is not a radioactive shipment.

[scooter]

Sorry that the question was confusing.  But the simple question is the question.  Fast, if you are at a DOE site, I would ask that you explore what your DOE rep says about your statement, ours will NOT agree that an DOE Order (5400.5) can overrule a LAW! (49CFR173).  Shipping - the word just gets in the way.  Anytime you release equipment you are allow and saying to the person actually shipping it that it meets DOT limits.  You might want to read the fed reg dated January 26, 2004 and especially look at the defn of contamination, SCOI and SCOII.  I agree 100% with your logic but at the FED level (at least not at all locations) it is not being recieved well and concurred with.

[Fast Fission]

I need to modify me answer. After reviewing Federal Register January 26, 2004 and Rev 2 of DOE Order 5400.5, I quoted an incorrect number in my response. The DOE 5400.5 limit for Removable contamination is 1000 dpm/100 cm2 not 5000 dpm/100 cm2. Changing this in my answer makes the DOT limits 2.4 times the DOE limit, so if something is released under 5400.5 it will also be under the DOT limit 49CFR173 for SCO.

I may still be missing something but the current DOT limit is 2200 and it is actually increasing to 2400, so how is it causing concern?

I don't deal with shipping much so maybe I am not seeing the BIG PICTURE.

[scooter]

It actually gets stranger.  Try a P-10 gas cylinder survey for release back to the vendor.  The definition for contamination is 2,400 dpm/100 cm2 per the new DOT Reg.  Per the REG, if it is between 2400-24,000 dpm/100 cm2 it can be shipped as SCOI(see SCOI defn).  That is the problem.  It is contaminated at 2,400 dpm/100 cm2 not 5,000 dpm/100 cm2.  One has to be able to prove that the cylinder has <2,400 dpm/100 cm2 to be released and not shipped as SCOI.

[Fast Fission]

But the DOE limit is 1000 not 5000.

[scooter]

Fixed + Removable = 5000 dpm/100 cm2
Removable = 1000 dpm/100 cm2

[cobrakid]

Dont confuse DOT shipping regulations and DOE or NRC free release limits. A radioactive shipment is not the same as a free release.

[Fast Fission]

DOT removable 2400 dpm/100 cm2

2400 > 1000

So DOE free release is below DOT limits.

[freerl]

First ever reply to anything:
How about you do what your supervisor/local procedure tells you to do, (get sign-off!), and leave the theory/philosophy to those that are paid for that?

[PWHoppe]

Freerl,

Very good first time post. I agree. Let those that sign on the line make the call.

[UncaBuffalo]

First ever reply to anything:
How about you do what your supervisor/local procedure tells you to do, (get sign-off!), and leave the theory/philosophy to those that are paid for that?

Actually, I feel that the "theory/philosophy" is what makes RP (AND this forum) fun, so you don't have to pay me to discuss them...

If you don't understand the REASON you are doing an action, you need to discuss it...it's called "having a questioning attitude" and is what keeps you AND your supervisor AND the work group out of trouble.

Sorry, I'll get down off my soapbox now.

[PWHoppe]

Climbing on a soapbox is fine if you don't fall off. Also having a discussion on limits and values is meaningless if you are not knowledgeable on ALL the regulationtions. DOE people are NOT shippers and shippers are NOT DOE people. The reasons for the many different levels are confusing but that is why there are people who are certified radioactive material shippers. They would be the ones who would sign the shipping documents and state the case for the material to go down the road. That is why I said let those with the knowledge sign for the survey. It is OK to have a questioning attitude and I'm sure they would be happy to explain why they are allowing this to go or not to go. Waste is a tricky thing, it is not just based on they dpm's per se but can also take into account the isotopic mix of the material. From what I had read in this thread no one had the requiste knowledge of shipping regs to comment on a factual basis other than to read quotes not knowing ALL the facts. I also assumed (probably/maybe) incorrectly that no one responding was a radioactive material shipper. If so I apologize but it appears that those asking and replying are mixing apples and grapefruits. There are many, many variables that go into the answer to the question and I would suggest getting with your rad. shipping personnel.

I guess I just fell off my soapbox.

[freerl]

UncaBuffalo,

Point well made! I guess I should have been more succinct in my post. I totally agree that discussion and a questioning attitude is crucial to our trade. I only meant that while we are questioning and discussing these issues, ( of which there are many, and far-ranging topics), a technician can rarely go wrong by simply following the written/verbal instructions supplied for that particular scenario by the powers that be. I'll try to be more concise in the future.

Roger

[Rennhack]

I will try to make this as clear as possible without joining the pile on.  I recommend you read this publication for a VERY good explanation:

http://www.nukeworker.com/study/hp/rct/lanl_p2_pdf/212_sg_1999.PDF

First of all, if you are at a DOE site, doing a radioactive material shipment, you are not doing a free release, so the free release limits don’t apply, because the material is not being released as uncontaminated or non-radioactive. They are going to slap a class 7 sticker or placard on it, perhaps an “Exclusive Use” sticker and send it down the road with its shipping papers.  It might go LAW instead, depends on the limits.  – Again, this is important, it is not being declared as non-radioactive, or non-contaminated. You are putting radioactive material in a “clean” container to ship.  The DOE may require that the outside of the container be released to the DOE “Free Release limits” (I would)… but it isn’t required, because again… its not being declared as “clean”, just as shippable radioactive material.

Next scenario… You “Free release” a widget that is 4k DPM beta gamma fixed.  It gets sold at a rummage sale, and the seller wants to ship it to their grandma in Kansas.  It is a clean little widget that has no rad markings, because it isn’t. You think that the “External Surface Limit” of 2,200 DPM is in violation… It’s not, because the  “External Surface Limit” only applies to radioactive material, and with 4k dpm fixed it is FAR below the definition of radioactive material. (Unless perhaps it was a feather reading 4k dpm/100 cm fixed)

Radioactive Material (49 CFR 173.403). Material or combination of materials which spontaneously emit ionizing radiation. Material with an estimated specific activity of less than 0.002 µCi/gram, essentially uniformly distributed, is not considered radioactive only by the U.S. DOT regulations.

More information…

The old DOT 2,200 Beta Gamma DPM limit (Same as the new 2,400 Beta Gamma DPM) is an “External Surface Limit” (Translated, “Smearable”) for “other shipping methods”.

Exclusive Use, Closed transport limit is 22,000 DPM/100cm2 beta gamma “External Surface Limit”, and the craziest limit of all, the “EMPTY” package, that can have 220,000 DPM/100 cm2 beta gamma internal surface.

One more thing to mention…  Packaging… Everything has to be packaged, so you will never come in contact with the actual radioactive material.  The DOE limits of 1k smearable beta gamma and 5 k beta gamma total for “Beta-gamma emitters (nuclides with modes other than alpha emission or spontaneous fission) except Sr-90 and others noted in the regs. Includes mixed fission products containing Sr-90.” Is much lower than the DOT limit.   You REALLY don’t need to worry about it. 

Also, your DOE 5k total… that is actually averaged over 1 meter, with a max of 15k DPM in 100 cm…

[Rennhack]

100 cpm = 1000 dpm (PER 100cm2).

You had many questions mixed together in your original post.  The 100 net cpm/probe on a pancake probe (~15.5 cm² area) = 1000 dpm/100 cm² is dependant on the isotope mixture.  The 1000 DPM number assumes the typical mixture at a power plant, and many areas at DOE sites.

Action level (cpm) = [site criteria (dpm/100 cm²) x E x G x T] + B
 T = Count time (minutes)
 E = Operating efficiency (counts/disintegration)
G =Geometry (detector area (cm²) ÷100)
 B = Background (cpm)


You Calculate dpm/100 cm² by subtracting background from the total count rate to obtain net counts and applying appropriate time, detector efficiency, and detector area factors.

dpm/100 cm² = R-B / E * G
         Where:
         N   =   net counts (counts)
         T   =   count time (min)
         R   =   total count rate = N/T
         B   =   background count rate
         E   =   operating efficiency (counts/disintegration)
         G   =   geometry (detector area (cm²) / 100)

It would vary for a hard beta vs a soft beta, they have different detector efficiencies.

[wave_theory]

Nice job explaining , Mike, just one small correction (I believe)

You stated:
"The 100 net cpm/probe on a pancake probe (~15.5 cm² area) = 1000 dpm/100 cm² "

Actually should read "The 100 net cpm/probe on a pancake probe (~15.5 cm² area) = 5000 dpm/100 cm² "

If you have 13% eff it puts you right at it, most places use 10 % to be conservative.

[UncaBuffalo]

UncaBuffalo,

Point well made! I guess I should have been more succinct in my post. I totally agree that discussion and a questioning attitude is crucial to our trade. I only meant that while we are questioning and discussing these issues, ( of which there are many, and far-ranging topics), a technician can rarely go wrong by simply following the written/verbal instructions supplied for that particular scenario by the powers that be. I'll try to be more concise in the future.

Roger

Karma Onya!  (and on PWHoppe)   

[MrHazmat]

As of October 1 2004 the DOT definition of Radioactive material has changed.
It now reads:
any material containing radionuclides where both the activity concentration and the total activity in the consignment exceed the values specified in table 173.436.
Explain: each isotope now has its own limit, most were increased, but a few were decreased.

An yes some of the DOE release limits are above the DOT limits which could get you a DOT fine if it gets caught on the road.

[Rennhack]

Someone at work mentioned the moratorium, stating that there is no release criteria. 

He suggested you look at DOE 5400.5 requirements for release of control of property containing radioactive material.

Of course, the moratorium only relates to waste, and not release of potentially contaminated equipment, such as your clipboard.