Re: ALARA at hospital

[Chris Davey <cdavey@med.phys.ualberta.ca>]

When our facility was renovated three years ago, we were told we could not
have stainless steel sinks and shower stalls or anything else that would
make the room look 'institutional'.  Covering the floor was likewise
frowned upon, because it would look so 'unfriendly', and might cause
people to trip and fall.

We eventually pursuaded admin. to allow us to replace the 'pretty' sinks
with stainless steel ones, reducing the clean-up time significantly.  We
are in the process of painting the walls with an epoxy (gloss) industrial
coating, which should make the clean-up time for walls shorter.  We are
also trying a new 'sealant' on the floor to see if it will prevent the
iodine from being absorbed into the flooring.  If that doesn't work, we
will try to convince admin. to allow us to try covering the entire floor
with 'Kaydry Lab Cover', which seems to be the cheapest we can find.  I
estimate it would cost $60 Canadian to cover the floor for each patient,
and guesstimate it would take a couple of techs the best part of an hour
to apply it (tape it down), so that the furniture doesn't rip it up, and
the patient/visitors/staff don't trip and fall.  Obviously this would be
preferrable to spending hours decontaminating the floor (sometimes
unsuccessfully).  Nevertheless, the tech time is not insignificant, as
sometimes we may have 5 iodine patients in one week.  (Most rooms clean up
quite well, maybe one in ten patients result in a problem).

The point that I haven't made (very clearly) yet, and the bit that this
ALARA thread brought to mind, is our licence condition, that says fixed
contamination must be less than 50 microR/hr for the room to be released
for general use once more.  If a level of 100 microR/hr was found to be
unremovable, it is easy to see that a typical patient stay (100 hours)
might result in a whole body dose of about 10 mrem.  This is my point -
such an additional dose is insignificant (we all know how easy it is to
get 10 mrem in day-to-day life) and seems completely 'over the top' in
terms of a reasoned response to a 'hazard' of this level.

If, for whatever reason, the room is put 'out of service' while the fixed
contamination decays away, we lose about $1000 US a day that such a room
would bring in, we risk running out of rooms (not many empty at the best
of times) and also we stop the peaceful characteristics of a private room
being available to our terminal patients.  (We do charge much more to
'foreign' patients)!

So, why do we really have to consider making the room look like the inside
of a parrot's cage, when the actual risk, even applying the LNT
hypothesis, is so small?  Is this really 'reasonable'?

Chris Davey

(I have made some more comments in Scott's response - see below:)

On Wed, 10 Dec 1997, Scott D. Kniffin wrote:
> Has every one forgotten what the 'R' means?
Good question!
> In my not so humble opinion,
> it is most certainly not reasonable to delay new patients coming in for 
> thyroid therapy.
Unfortunately it happens.
> I don't know what your room protocol is like, but you 
> might try covering the floor in absorbent paper and lining the bed with 
> a plastic sheet. 
We have a whole floor of unusable (politically) patient rooms,(no funding
is available to provide nurses for the unusable floor), so not only
can we put the mattress in a liner, we can swap and store any room
furniture, so that does not prevent the rooms being reused immediately.
> Thus when the patient moves out, you clean up the paper 
> and sheets, store THAT for decay somewhere and the room turn around could 
> be reduced to one day following a room inspection by your HP's. 
Rooms are turned around in a matter of a half hour or so, after
non-radioactive patients.  If we used the paper floor covering technique,
turn around might be as long as half a day, hopefully no longer.
> As a plus, 
> the week that you wait for the trash to decay will save the expense of 
> sending the stuff to the Canadian equivalent of Barnwell.
With a half life of 8 days, the current storage of contaminated linen,
etc., is for ten half-lives, or 80 days.  The paper would have to be
stored for the same amount of time, and additional storage space would be
needed.  We certainly could not consider sending any of this to 'the
Canadian equivalent of Barnwell' (Chalk River, AECL, Ontario, I suppose).
 
 > The increased 
> cost of lining the room should be significantly less than the loss of 
> revenue from not using the room for a week.
That's very true.
> With this method maybe the person(s) who clean up the room will have to 
> spend less time in the room, (i.e. peel, bag, meter and go) decreasing 
> your dose to personnel, making everyone (including AECB) happier.  
As the dose rates before decontamination is started are rarely more than 2
or 3 mR/hr, the actual dose to the tech.s as they clean the room is not
really a great concern.  Again, this would be ALARA for its own sake,
reducing a dose from maybe 1 or 2 mrem to 0.5 to 0.8 mrem (for example).
I think a lot of the experts on this list would say even a one dollar
expense to achieve this sort of reduction would be too much!
> That might be considered reasonable, no?
> I calmly await the storm,
> Scott Kniffin
Thanks for your comments; I hope they'll generate more discussion!
> At 10:44 12/10/97 -0600, you wrote:
> >Here's an example from medicine:
> >We treat thyroid patients with I-131.  Afterwards, invariably the patient
> >room is contaminated.  The AECB (Canada's equivalent to the NRC) requires
> >us to decontaminate before the room is reused.  The limits are ALARA
> >inspired, and are much lower than the annual limits for MPD in the
> >regulations.  Because we cannot always decontaminate to these levels, the
> >room is often 'closed down' for a period of several days or weeks to allow
> >for decay.  Thus we:
> >1	spend a great deal of time and money trying to meet the ALARA limits,
> >2	lose a room, resulting in delays for admitting new patients
> >3	lose the revenue from the private room
> >There are other aspects, but hopefully this gives you an idea.
> >Regards
> >Chris Davey
> >        RSO  Cross Cancer Institute  11560 University Avenue
> >        Edmonton   Alberta   Canada  T6G 1Z2
> >        (403)432-8616   fax 432-8615    email cdavey@med.phys.ualberta.ca
> >        pager number 005, just call (403) 432-8771 and ask for that pager