[R-390] R390A meters

[Charles Steinmetz]

Several people have contacted me offlist asking how much risk there is 
if one *does* open a radioluminescent 390/390A meter.  This is a very 
tough question.

My answer is:  I know nothing about you, or your abilities concerning 
careful detail work that requires fine dexterity and hand-eye 
coordination, or your ability and willingness to follow instructions 
down to the last detail.  Therefore, I must recommend that you *DO NOT* 
open a radioluminescent 390/A meter *for any reason*.

If you decide to ignore this advice and *do* open such a meter, you must 
absolutely, positively insure that you are the only person who could 
possibly be exposed or endangered by your activities. I also recommend 
that you *study* (not just "review") the AEC/NRC cleanup protocols, as 
well as the standards and protocols that govern working with materials 
that contain Ra226.  You will also need to ensure that you have 
laboratory-grade radiation monitors ($$$) available at all times.

At a minimum, you will need an indoor space that is relatively well 
sealed (doesn't exchange air with the outside environment).  You will 
need to enter this space and seal it up, and have available at least one 
laboratory-grade radiation monitor (preferably two, for sanity checks). 
  You will also need to have a reliable communications device you can 
use to contact your local HAZMAT authority, as well as the contact 
information for that authority.

This means that no part of any dwelling occupied by others may be used 
(whether they are there at the time or not).  *Period*.  You at least 
need a standalone building (preferably small) located at least 50m from 
the nearest other building.

So, the drill is:  Seal yourself in and do your work, continuously 
checking the radiation monitors.  Clean up, putting all leftover 
radioactive materials into radiation-safe containers that are shielded 
for the types of radiation emitted by the item(s) you were working on 
(alpha, beta, and gamma in the case of Ra226).  Check for residual 
radiation *everywhere* in the space you are working in, including your 
own person and clothing.  Check again.  Check a third time.

If everything tests clean, arrange to have your local HAZMAT authority 
pick up the waste container(s) (or transport it to them, if permitted in 
your jurisdiction -- but be sure to *CALL FIRST* to alert them that you 
will be coming).

Now, here is the hard part.  If there is any residual radiation, *STOP* 
before you spread it any further.  Call your HAZMAT authority, explain 
the situation to them, sit down calmly, do not move or stir the air, and 
wait patiently for the nice people in radiation suits to come and 
decontaminate you and your space.

Now, do you still want to open up your meter?  If so, (1) keep your eyes 
wide open, (2) take full responsibility for what you are doing, 
understanding that radioactive dust is easy to spread and virtually 
impossible to collect after it is spread, and (3) take all of the 
precautions described above.  I have done this in the past, but I would 
not do so today because my manual dexterity may no longer be up to the 
challenge due to aging.

Better, look at *how nice* Bob's replacement meters came out, and follow 
his lead.

Best regards,

Charles