This can get into a really complex issue and one with no easy answer.
Generally, (depends on the isotope) 5 k average, 15 k max.
Hey DOT say's 22 dpm/cm2 Alpha , 220 dpm/cm2 Beta-Gamma , and 0.5 mRem/hr is clean :Ddis iz what dot is sayeen these daze? i thought it wazant crapped up until it waze, like, 22k or so, betagamma external to da package?
dis iz what dot is sayeen these daze? i thought it wazant crapped up until it waze, like, 22k or so, betagamma external to da package?
The limits I posted are in cm2 not 100cm2, so actually it's 22000 and 2200 dpm/100cm2Perhaps you meant 2200 and 220 - know as Return to Service (RTS). DOT's way of saying clean. We recently asked them about it because it conflicts with NRC (None detectable). They reconfirmed that RTS is acceptable to send back to Mom and Pops Crib and pacifier shop.
Perhaps you meant 2200 and 220 - know as Return to Service (RTS). DOT's way of saying clean. We recently asked them about it because it conflicts with NRC (None detectable). They reconfirmed that RTS is acceptable to send back to Mom and Pops Crib abd pacifier shop.
49CFR 173.443You left out 173.443 (a) 1 where it gives the 10% efficiency
(c) Except as provided in paragraph (d) of this section, each
transport vehicle used for transporting Class 7 (radioactive) materials
as an exclusive use shipment that utilizes the provisions of paragraph
(b) of this section must be surveyed with appropriate radiation
detection instruments after each use. A vehicle may not be returned to
service until the radiation dose rate at each accessible surface is
0.005 mSv per hour (0.5 mrem per hour) or less, and there is no
significant removable (non-fixed) radioactive surface contamination as
specified in paragraph (a) of this section.
(d) Paragraphs (b) and (c) of this section do not apply to any
closed transport vehicle used solely for the transportation by highway
or rail of Class 7 (radioactive) material packages with contamination
levels that do not exceed 10 times the levels prescribed in paragraph(a)
(a) The level of non-fixed (removable) radioactive contamination on
the external surfaces of each package offered for transport must be kept
as low as reasonable achievable. The level of non-fixed radioactive
contamination may not exceed the limits set forth in Table 9 and must be
determined by either:
(1) Wiping an area of 300 cm\2\ of the surface concerned with an
absorbent material, using moderate pressure, and measuring the activity
on the wiping material. Sufficient measurements must be taken in the
most appropriate locations to yield a representative assessment of the
non-fixed contamination levels. The amount of radioactivity measured on
any single wiping material, divided by the surface area wiped and
divided by the efficiency of the wipe procedure (the fraction of
removable contamination transferred from the surface to the absorbent
material), may not exceed the limits set forth in Table 9 at any time
during transport. For this purpose the actual wipe efficiency may be
used, or the wipe efficiency may be assumed to be 0.10; or
(2) Alternatively, the level of non-fixed radioactive contamination
may be determined by using other methods of equal or greater efficiency.
Table 9 is as follows:
Table 9--Non-Fixed External Radioactive Contamination Limits for
Packages
------------------------------------------------------------------------
Maximum permissible
limits
Contaminant --------------------------
Bq/cm2 uCi/cm2 dpm/cm2
------------------------------------------------------------------------
1. Beta and gamma emitters and low toxicity 4 10-4 220
alpha emitters..................... .........
2. All other alpha emitting radionuclides.... 0.4 10-5 22
------------------------------------------------------------------------
If you follow this completely you come up with 2200 and 220,(10% Eff.) but if the limit is 220/cm2 and you have 100 cm2 you would actually have 22000 dpm/100cm2. Not easy to understand if you are not use to dealing with Lawyer written regulations.
Most LTPs are written using the 25 mr/yr criterion. A Resrad is run using the resident farmer senerio to give you the DCGLs for the 25 mr/yr and then you are finished. Wrong! The state EPA and DEP looks at that and makes their determination. Some give and take goes on (mostly give) and a final criteria is decided on. Some states are going to a 10 mr/yr criteria and in some instances materials must meet a 1 mr/yr.
AA,
You may be on to something with the Release Criteria based on Occupations! I don't believe you could ever include lawyers in the D&D equation. If you interjected lawyers into the calculation, " Worth vs Risk ", you would be Free Releasing the Commercial Plants at 100% Power!
Sorry, but I couldn't resist, RG!
OK, thanks. But to get back onto the topic, how much can one leave behind as clean with a delicense operation? Could we assume that 100K/100 cm2 of Co60 would be OK? Could we go to 150K if it was only U238? What would the transuranics work out to?
I have to admit total ignorance when it comes to D&D work, but if 100K/100cm2 of Co60 is releasable anywhere, then what the hell are we worried about releasing items and areas that are over 1Kdpm/100cm2 in the commercial end of the world? Or for that matter having release limits of 'No detectible activity' even considered if we are just going to release it all later at 100K?OK, I may have gone overboard with the 100K Co60. When we were sitting around (originally, please note starting post) finishing off the meager stash of XX and 1812 in the local tavern, we started messing with numbers. I believe the we figured we could do at least 50K dpm/100cm2 direct read.
That does not compute...
I agree about NRRPT $$$$ (cause I am one) but it doesn’t' detract from some of the excellent seniors I have known that weren't mathematical enough to pass the test but could cover a job like a lead blanket and protect the workers better than an egg head that could pass the CHP but couldn't find a hot spot or understand the work flow for an outage. People are people and you can't test ethics and job coverage. 90% of the NRRPT test had nothing to do with power plant outage health physics. Maybe if the pool of technicians were all interconnected so each 'dirtbag' identified at one plant could be noted at another and soon wouldn't be hired by any, it would help. But it won't happen. We're stuck, so just do your best, teach the best, accept only the best, encourage the best, and hope for the best.
hey atomic the question has been answered several times. its nudlide dependent, agency dependent, statistically dependent, politically dependent, and instrument dependent. now back to the question i asked, are you looking for pollution indications or to apease the regulators?
if you want us to design your DQOs and determine your DCGLs ya got to give up da green$$$$$$$$$$$$$ cha-ching
You are welcome to make up your own scenarios.
what do you have to run resrad 'n a resident farmer scenario? wut iffen yer ona site that ain't never gonna revert to farm material?
No Washing the Uranium with Radium water :o They had a device in the 1930's I guess was the first attempt at hormesis. The revigarator or something like that. Unfortunately the radium in the water depositd to the bone. This is not good. So the hormesis I believe should be called vitamin R, and should only be a external small radiation source and standards set by FDA :P. No radium water to wash or grinding of the uranium to make a internal dose :P Vitamin R How clean is too clean?
No Washing the Uranium with Radium water :o They had a device in the 1930's I guess was the first attempt at hormesis.
You answered your own question, "All final status surveys completed" Which means it passed what ever criteria established.Scrabbler, are you? Where I have worked, Final Status Survey is the last survey done. Then the paperwork is compiled and submitted. Then the license goes away, or not. The survey completion does not necessarily indicate that passage has occured.
Gosh i love playing with the words.
This is what is ridiculous about e-6 release levels. These limits were created for man-made stuff, like solvents and acids and such. These things have no background, so they are easily measurable on the Earth at e-6 levels. Radiation is present all over the planet.
Younz havta prove that tha place won't ever be used for agriculture. Try ta get a regulator to sign off on dat.
and how does the concept of -dpm's fit into this?....as in 167gcpm(measured)-240cpm(bkg) /15%(eff)= -487 dpm
::)
Or better stated how hot in R an Hour for a tank to start crossing this fallout zone so that it is clean enough not to exceed the mission limit of 150 R Dose?As a nuclear target analyst, I would advise the coffee drinking General staff to utilize the weapon that would give a (3) to the overrun attempt troops, while maintaining a level (1) for our troops.
How about troops? How hot is clean?
You are a nuclear target analyst, You Advise Generals on how close to drop nuclear weapons to your own troops. You have three criteria, 1 negligible risk which means slight risk to your troops, 2. Moderate Risk some risk to your troops and 3. emergency risk which means you may have to wipe them all out. You are drinking coffee with the General staff about 15 miles from ground zero, Your 10,000 troops are about to be overrun by 100,000 troops. You make the call!! How hot is clean??
Your Sub Base in the USA is being over run by fanatics, They get a hold of some nuclear subs with nuclear weapons and head out to sea. What is the smallest nuclear weapon you can drop on your homeland? How hot is clean? 1KT 100 KT 1Megaton?
You see a Mushroom cloud with the wind blowing in your face. A few minutes later your tactical dosimeters purple viles all turn gold. You start blowing chunks, does 5K 15K matter?First part; I wouldn't worry about 5K or 15K while chunk heaving, unless, of course, the units were R/hr. Even then, my worry would not consume much of my thought process.
Your in a Helicopter flying across a fallout zone doing air to ground coorelation factors and the fallout is reading 100 R on the ground. When do you start letting your tanks drive through this? how about infantry walking through this. hint, There is a 7 10 rule for fallout which means for every 7 hours your fallout decays by a factor of 10, Tanks provide shielding of 90 percent, troops no shielding, troops walk at 4 miles an hour, tanks go at 45 miles an hour, the fallout zone is 10 miles across, also as you enter the fallout zone the fallout is decaying as you walk or drive. Also your troops tactical dosimeter is already reading 50 R. You only allowed another 100 R to complete your mission for a total does of 150 R. The tank is obvious, What about the troops??
hmm I think the DQOs were inadequate if you completed the FSS and it failed criteria and the surveys were allowed to stand without remediation. Seems like the developers of the DQOs were not well versed in this process. Surely they didnt use the WRS if you did ya gets what ya wanted. Also, sounds like the characterization was inadequate. Take for example ETTP, the whole project was based on 3 or 4 swipes and characterization of 1/100 of the structure. The contractor that was assigned FSS did rather well in this case. The other contractor that belived what the client belived in lost cedibility and tons of money. Aint that da truth Shonaktoys???Oh, my! I thought I had provided enough information for you to play. Obviously, not. Let me paint a broader picture for those who are imagery challenged.
As for leaving a hot spot.. shame on the contractor..simple areas like a hot spot can be remediated and must be considered in DQO design.
As for challenging a regulator.. is that the voice of inexperience???? You correct regulators, you inform regulators, you educate regulators, you agree with regulators and you listen to regulators-never, never challenge regulators.. If you have to do that, your DQOs were poorly designed to begin with.. (low bid again)
Why, I believe that concept would enter into this via "averaging".but how do you average something that doesn't exist?
but how do you average something that doesn't exist?
Younz havta prove that tha place won't ever be used for agriculture. Try ta get a regulator to sign off on dat.
Welcome to the world of statistics and analysis. The concept of "-dpm's" does exist. After all, you measured it, correct? Simply because a value is less than the background value, doesn't mean it doesn't exist. It simply means that it is a different value. Let me explain it this way. When you run a background for an instrument that will be used in a survey which will be of a reportable nature, ala Final Status Survey, it is customary to run a background count time of ten times the time to be used for the counting during the survey, then average for a one minute count rate to be recorded as "background". Since survey counts are of a one minute duration, therefore the background count rate is to be run for ten minutes. During that ten minute span, there are ten one minute segments which integrate during the time frame. If you were to separate the segments and look at the individual counts, you would notice they do not equal the background count rate, some would be greater than and others less. So if during your survey you wind up with a count rate that is less than the background count rate used for the day, it is a normal counting function for that instrument. You must record this count rate in order to maintain statistical accuracy of the survey. Using "less than background", "zero dpm", "below detectable limits" all throw the survey into question.good answer, but that's not the way they had us do it. a bkg was 'assigned' to the instruments (all the instruments of the same model) based on the material (steel, concrete, transite walls, etc.). this did not change on a day to day basis....in fact, the only time it changed was in the middle of the project when they changed all of the instrument eff.'s but didn't change the backgrounds....the net result being an increase in the activity 'assigned' to 'background'. we were told by the largedollarpeopleintheaircond itionedtrailer that the backgrounds were based on the amount of NORM that is present in the building material (the NORM norm?), which seemed to change in the middle of the project :o. I disagree with your contention that conventional practice of using the MDA value for those counts showing less than MDA (or <Bkg) would reduce the statistical validity of the survey. In fact, entering values that you cannot possibly measure with accuracy, or which don't really exist (such as - dpm's) artificially biases the evaluation to the low side.
In fact, entering values that you cannot possibly measure with accuracy, or which don't really exist (such as - dpm's) artificially biases the evaluation to the low side.
'n yz think dat giving a false numerical value doesn't artificially biase the evaluation to the high side? yinz had better show da math on dis won!Any 'false numerical value' will artificially bias the data, but using MDA when your results indicate <MDA is not 'false.' It is the most statistically valid number you can use under the circumstances. Also, it seems to me that when evaluating any health hazard it's better to bias high than low.
Any 'false numerical value' will artificially bias the data, but using MDA when your results indicate <MDA is not 'false.' It is the most statistically valid number you can use under the circumstances. Also, it seems to me that when evaluating any health hazard it's better to bias high than low.
When we were told to use -dpm's I posed the question "If a D is the movement of an unstable nucleus toward a stable state, wouldn't a negative D be the movement of a nucleus toward a more unstable, or radioactive, state?" ;)
They said "shut up and do it."
Any 'false numerical value' will artificially bias the data, but using MDA when your results indicate <MDA is not 'false.' It is the most statistically valid number you can use under the circumstances. Also, it seems to me that when evaluating any health hazard it's better to bias high than low.
When we were told to use -dpm's I posed the question "If a D is the movement of an unstable nucleus toward a stable state, wouldn't a negative D be the movement of a nucleus toward a more unstable, or radioactive, state?" ;)
They said "shut up and do it."
which brings us full circle- any found is a pollution indicator. the world is polluted by nuclear technology- fall out from weapons is readily detected in game and hunters, chernobly spread a nice wide band over the southern US, SNAP reactor and Russian reactor burn up in the atmosphere makes plut some what easy to find. Now, what is the risk.. that is the question that should be asked. 25 mr/yr is a good number, 10 mr/yr is politically correct. nuff said?This is an interesting hang-up of yours, pollution. Using Webster's New Third International Dictionary, one finds the #1 definition as "emission of semen than at other times than in coition." An interesting picture that you paint. However, since radiation has been present on the face of the planet for as long as you care to measure, I am unsure of the relationship.
...Sorry you have AADD.
Edited because modertors rule.
well, pollution indicators are for most of us the way we make a living, including you atomic.
I journeyed through this site, but was unable to locate Moe. "Darn", says I.
come on guys dont be so narrow scoped. as scientists and engineers we are trained to view the total risk of what we do, pollution indicators typically describe "man made stuff that has left the building." Man made rad materials are CERCLA listed and have RQs and are therefore deemed by law as harmful pollutants or hazardous substances. the dictionary I use (American Heritage) provides one definition as "the contamination of soil, water or the atmosphere by the discharge of harmful substances."
clean does not equate to hot in any degree. its either contaminated or its not. 0.1 pCi/g of Sr90 in soil indicates contamination (pollution indicator). now the risk is another story! (1.6 mr/yr)
If you look at the JPG to the left very carefully you will see were some drums were sitting. These are white and orange rings with other contamination left over from drums in this area. This is Hot!!! The Black areas are clean!!!! How hot is clean, The black areas are less than 5000 dpm 100 cm2 and therefore clean!! IT is probably hot where these drums are at!!! LOL What great HPs these were!!!:'( [Hey did someone frisk these drums? Its OK (Put in favorite dirt ball)I say!!!]
well pollution indicators designate a scope beyond nuclear power plant mind set, so i can see the resistants to a total risk method. But CERCLA listed items they is..
Oh yea, NPDES lists rad materials too...hmmmm wonder why???
no slo go the news only took pictures of the 5 mr/hr blocks and the pit dug in the guys yard down the road. what do they know! I guess the give away was the rad materials sign and ribbon they found from the plant that was burried 6 feet down.
The Knoxville Sentinel had on the front page that Bechtel Jacobs had about 100 Alpha instruments that they do not know how long they were not working. So how hot is clean. Hmmm it depends on what meter you were using, and if you know if it was working or not.Well, yes. I thought we were working professionals here, not media reporters. ;)
well archy, its too hard to explain how we do our jobs here in a few paragraphs. it takes some of us days, weeks, months to determine what dose a few thousand dpm of some nuclide will deliver over a 1, 10, 25 year period... thats why we make the big dollars$$$$)
seems to me it all "....depends on what your definition of is is....",.....Are you running in '08? You have my vote!
If you look at a cumulative frequency distribution from a modern instrument you will see that about half the readings will be below 0 if the material is not contaminated, or slightly contaminated. Anything above 15,000 dpm 100 cm2 or above is hot for certain isotopes, 14,999 is not. A cumulative frequency distribution can be viewed by clicking the Nukeworker tool bar, Pictures, Then go to Nuke companies, then click Shonka. We have actually fired someone by looking at this distribution and seeing the background was wrong. We checked that person in the field, Sure enough he was cheating, TOO BAD out the door. You can't get this with 1940's technology that most people still use.
Real release and risk is what you can convince your neighbors of.
.My only hope is if this has been a continuos discussion since your celebration of Cinci De Mayo you call a taxi to get home safely.
People want me to prove that a tiny amount of radiation will not harm people every day. For those opposed I say prove that it does harm Humans. All you have is speculation.
and if you had said that in 1950 about asbestos, what would the results have been? :obout the same as iffen ya say the sun's rays won't hurt ya when yer ina tanning salon!
IReal release and risk is what you can convince your neighbors of. If you have people sending out flyers convincing you neighbors that they are going to die if they buy property on your released land, you are in huge trouble. Most Humans will accept the worst story as true.
That would mean we would have to move to the moon and bury the Earth on Mars. That way everyone would be safe, right?
bout the same as iffen ya say the sun's rays won't hurt ya when yer ina tanning salon!gotta agree with ya, glo......the sun's rays won't hurt ya when yer ina tanning salon (or a koal myne, or on a SG platform) ya mite wana wach out fer d'bulbs tho'
Risk? How about the 2 pack-a-day smoker who is afraid of nuclear energy due to "radiation". They are shocked to learn they get more than me. One worker would come to work and light up the PCM. It ended up his basement was smoking hot (radon). Plainfield Il had to go to Lake Michigan water the Ra was twice EPA limit for radium in the water supply.
If you established a release criteria of 10% of the current models, your probably still to high!
i dont think you can sell your liability slo go.. out of sight dont really mean out of mind.so iffen the regulators buy off on the license 'n it is terminated, 'n i sell the property, i'm still liable? i think i know what the donald would tell the engineers that negotiated with the regulators.... do yew?
under nuke no you are not but a holding company is as well as the underwriter. for RCRA yep you are!explain this, as you lost me. when a license is terminated, and then the property is sold, then the criteria changes, who is liable? the licensor?
Who would have thunk that I would have lived this long, to see that happen, LOL?
I'm not sure, but I think the 'cradle to grave' concept applies to nuclear material as well as all other contaminates (pollutants?)....you know the drill, once it's yours it's yours forever
confusion of issues slo go. brownfields are areas that are remediated and gone thru environmental restoration. we are talking about waste in the can here.yo, weight a minnit there, alphadude! i ain't confusing anything that you haven't muddled up already. you brought the pollution banner into this discussion. i was talking about a finalized, remediated nuclear site, a yellow/majentafield. i ain't talking bout no waste in no stinkin can! i used a brownfield as an example that is similar in nature, although the contaminate is different. p'rhaps yinz should go back 'n read my posts on 7/1/05 @ 14:24:18, 'n 7/1/05 @ 08:37:41. maybee it'll help ya. in the meantime, ya got an answer, yet? or ya just got more smoke to blow in front of yer mirrors?
rule changes, if there is an identified hazard after the fact may be under consent orders, SWMUs, or special ruling. if the owner disclosed properly and the property changed hands legally, underwriters would be bear the burden of the liability- (banks, insurance, bonds etc.)
mixed terminology does muddy the water-brownfields are not a nuke related-
if you sell and disclose properly-you are free!!
No smoke nor mirrors, just 32 years of dealing with epa, AEC, NRC, state and federal agencies and teaching environmental law for a few years.
I told him that I heard about the environmentalist that died in his hometown of Seattle. "He had a heart attach when he saw a Spotted Owl eating a Pacific Salmon." Now come on, that is funny!
but da coroner ruled he had an excessive uptake of iodine, ruling that it must have been the releases from the nuke subs ina harbor, ignoring alla salt on da environmentalist's dining table. karma to ya ray.
only when I'm within 100 miles of sloglo,....heheheheheheh,.....
Funny you should ask, here's my answer:
I have done this nuclear thing for many years and I still feel safe.
Sometimes, while poking around in old structures and finding >500KDPM I get a little nervous, but that's because I think of all the people who have been where I am that didn't have a meter, training, or the slightest clue. Then, when it's done, the fuzzies turn warm to the touch, again.
The scope of the question was somewhat gray but it did generate chatter.. which is always fun.
how hot is clean is basically contribution that would assume no more burden than provided by background.
a released nuke building for non nuke can be controlled by local zonning laws. The resident farmer example covers the building released for residential use. (25 mr)
Grand Central Station is not a living space. The "bag lady scenarion" was not adopted by regulators.
the 25 mr is above bkg.
So, how much contamination can a licensee leave on their buildings' interior surfaces? Depends on the radionuclide and the termination plan.
If you are allowed to leave 25 mr/yr, isn't that a lot more than 15Kdpm/100cm2 max per meter? Of what radionuclide?
Could we assume that 100K/100 cm2 of Co60 would be OK? Could we go to 150K if it was only U238? What would the transuranics work out to? What is the surface area?
I can see where someone who was playing with Th in Balitmore might have a problem with the questions posed. After all, I was laying with piles of Th in Baltimore Harbor in the mid 70s. If you are talking about WRG, this has been remediated and FSS. Levels of Th there were unacceptable and high risk. When we surveyed it, well over 100k dpm/100cm2 were found. (not fixed), and the area had been a work area for non-rad workers for years.(State of Md issue) That place is a legal can of worms.
If you are drilling for oil in maryland, take a short break to have your head examined.
you know spotted owl taste just like bald eagle.. kinda stringy
my reply is who cares?? NORMs have been lobbied hard by API and are laying around every where there is an old drilling station. those primordials are rather nasty. but unless its in a facility im doing D&D on..... cant see it from here.
yeah, ok. but iffen yer inna bkg like at grand central station, then yer fricken 25 mr/yr goes right outa the window, don't it now?
So, how much contamination can a licensee leave on their buildings' interior surfaces?
If you are allowed to leave 25 mr/yr, isn't that a lot more than 15Kdpm/100cm2 max per meter?
Could we assume that 100K/100 cm2 of Co60 would be OK? Could we go to 150K if it was only U238? What would the transuranics work out to?
my reply is who cares?? NORMs have been lobbied hard by API and are laying around every where there is an old drilling station. those primordials are rather nasty. but unless its in a facility im doing D&D on..... cant see it from here.
its all about LET. trout streams and drilling brine are not likely to be in the same area.yinz reely wanna geography lesson here? alls i get is that ya don't care what the dose is to the general public, long's it ain't isotopically tied to your pet project. so iffen ya pull over at a rest stop ona interstate, 'n walk thru alla dis mud 'n muck dat fell offa a drill rig, it'd be ok. 'n when yer shoes light up the frisker at the new job tomorry morning during g.e.t., wail, hail; whutz a guy to due but grin the grin?
I love it when these people insist I clean up to greater than common sense levels because my wife said she likes to sleep under a roof that doesn't leak and eat three times a day.
Why can't we all do intelligent and productive jobs and still get paid?
This is still a fun post.
howz come i ain't seeing no answers to da questions?
. We are all intelligent people. Why can't we all do intelligent and productive jobs and still get paid?the answer to that one is easy........we don't all work for intelligent people. (for SloGlo: wee doant all werk four intelagint peepl ;))
howz come i ain't seeing no answers to da questions?
Rad Tech, Rad Tech, what’s you going to do?
What’s you going to do when they won’t answer you?
since there ain't nuttin but people tellin everybuddy else that 'it's all what you can get yer regulator to agree to
would attending the five day anl class for six hundred dollars be worth it.
You seem to be dealing with building limits. Most people are dealing with soil limits. The problem is from State to State, the State regulations vary. In our State, we have a moratorium from the Governor that says that no debris from D&D may go to a regular landfill, even if you prove it clean through MARRSIM. We quit doing MARRSIM surveys on buildings. We just prove they are clean through DOE standards (we survey them like a tool going out of a control point, get the State's approval through their confirmatory survey and demolish the clean building and ship the debris to a controlled hazardous waste site. That site will not accpt the debris without a letter from the Stae regulatory agency. We are in constant contact with them. We get preapproval of our plans before we even start.
You wanted numbers. We are a DOE site, so our release criteria are based on DOE's basic release criteria. We never had pure strontium here so our beta release limits for the debris are based on a mixture of beta-gamma emitters. They are less than 5,000 dpm/100 cm2 when averaged over a one square meter area. You can have hot spots up to 15,000 dpm/100 cm2 as long as your average over one square meter limit is not exceeded.
I'm not meaning to butt in here, and my apologies to the Mssrs. involved. However, I believe this information would indicate that your answer to the original scenario (65K Co60) posed would be that it would not be clean.
I have been working the Mound site recently. Pretty interesting. 300 dpm max spot 100 cm square alpha and 100 dpm Can some one explain how a floor monitor is used with about 600 cm2 surface that can be rolled the right speed at all times and interplate 100 cm2 in it without looking for 1800 dpm 100 cm2 which would assume 300 dpm in each 100 cm2 of the cart?Without getting too rudimentary, one would use the floor monitor in a search mode at 1/3 probe width/second travel speed with the alarm rate set to the corresponding point. For those without the set point characteristic on the assigned meter, the observed rate for an alarm condition would have to be agreed upon. Once that count rate has been breeched, then the proper sequence of events would dictate the usage of a 100cm2 probe to survey the area detected by the large area probe on the floor monitor.
Yes, you are right, if RESRAD Build tells you for pure C0-60 that your limit is 65K dpm/100cm2, you are still limited by the basic DOE, NRC, EPA guidelines. That is 5000 dpm/100cm2 fixed for beta emitters, averaged over one square meter and no "hot spot" over 15K dpm/100cm2.. I don't see a way to get around this, and we have found that this is achievable here.
So I guess how hot is clean is what you get away with if no one checks or is too stupid to know the difference.
been dead,....it's startin' to stink to high heaven now
Pretty funny AA. I use rose colored glasses now to see the world in a different light. The chickens all look pink to me now, LOL! I do know what a white chicken looks like, however, if I take my glasses off. Good comment on current status of how hot is clean.
The state or DOE brings a high energy beta green chicken source NIST traceable source to have the fox check. The fox tells them it is 10,000 since he has a poor high energy beta green chicken checker when it is really 100,000. The fox has many options,...
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