DIZY4@aol.com asks:

>if you experience a power failure in the lab with no emergency power back-up
>what is the worst that would happen to tissues depending on station that the
>power failure occurred and how would one remedy this, (stations of alcohol,
>histoclear, paraffin). person arrives in lab around 6-630 am tissues start at
>7pm.

I believe all the current tissue processors on the market have battery
back-up so that when the power goes out tissues remain in whatever solution
they were in or at least in a closed, solvent-saturated environment. When
the power comes back on, they continue the processing cycle from where it
left off. I haven't heard of any tissues being damaged because of power
outages on closed system processors, but that doesn't mean it hasn't
happened. In the old days of open system tissue processors (Technicon Duos
and others), baskets could "hang up" during transfer and tissue would dry
out, sometimes damaging tissue.

>also this lab uses isopropyl alcohol and the 100 % cleaning station
>builds up with paraffin is this caused by the isopropyl and histoclear?
>thanks for any help you can give me.

Histoclear (and other Xylene substitutes) are less than half as efficient
as xylene at dissolving paraffin in the cleaning cycle. I believe your
problem is that the Histoclear cleaning solution is getting saturated with
paraffin and therefore, the paraffin ends up in the 100% isopropyl. All
tissue processor manufacturers recommend changing out xylene substitutes
cleaning solutions at least twice as often as you would xylene. In the labs
I've been in, many change their xylene substitute cleaning solution daily
and most at least every 2-3 days. This problem can cause solidified
paraffin to get up in the tubing and valves of your processor and require a
service call to clean it out.

Hope this helps.

Marvin Hanna