[adriponic]

hi John - Hi Nguyen

Ng 10% is, I would say, a high contamination rate. Going
to my records for the past 5 years the average contamination is as follows:-

Mother flasks (inclusive of tissue culture) 1,457
Mother flasks contaminated 36 = 2.5%

Replate flasks = 8,613
Replates contaminated = 69 = 4.75%

I work in a sterile room cleaned with a laminar flow
30 mins ahead of operations which are carried in a
sterile box.

John - I do not vent - All my flaskings are done in 800 ml
micro oven plastic containers filled with 100 - 150 ml
media. There is lot of air space inside so i do not have to
vent. The containers & media are sterilised in a 20 years
old home made autoclave which is gas fired. One run
can accomodate 20 flasks + utensils. Heat goes up to
123 celcius in 14 mins with just about 1.2 litres of water
inside. One run from firing to harbouring the flasks and
utensils inside the sterile room takes less than 40 mins.
However the flasks & covers have to be sealed with
sterile cling film in front of the laminar flow IMMEDIATELY
upon removal to the sterile room. Quite a hard job to
handle very hot plastic but I am now at ease with it
after some 7 years practice.

My son will visit me in a couple of hours. I told him to
bring his digital camera and i will have him take pics of
whole set up for posting.

Hope this helps - Kind Regards