14
THE GAS CIRCULATION SYSTEM
The fan units pick up the cooler incubator atmosphere which has been forced to the top of the incubator
and first passes it over the warm heater. This warmer gas is now forced down the channel at the back of
the cabinet then it passes under the bottom shelf of the incubator where it first meets the sachets of
Conditioner and then the sachets of Catalyst. The gas now gives up just sufficient of its heat to maintain
the required temperature before finding its way back to the top of the incubator due to the suctional force
of the fan.
CHANGING THE CATALYST AND CONDITIONER
The sachet of Catalyst and the sachet of Conditioner which are housed beneath the bottom shelf of the
incubator will require replacing at a period in excess of one year. If for any reason the sachet of catalyst
gets wet, the contents can be dried out by heating to a temperature of 160
°
C for a period of two hours.
The sachet of conditioner can, if necessary, be dried at room temperature. The chemicals can then be
returned to their respective containers for further use. .
When replacing the sachets, ensure that the sachet of Atmospheric Conditioner is at the REAR of the
cabinet so that the gas passes over it first. (See sketch below)
CLEANING
The inside of the cabinet can be swabbed out with a weak solution of general laboratory detergent and
warm water, and dried with a soft cloth. In the event of a culture spillage, a 5% Hypochlorite solution
should be applied to the area and left for half an hour. It should then be wiped and swabbed with a 1%
solution of Sodium Thiosulphate. Remove the catalyst and conditioner from the unit while the Hypochlorite
solution is being used.
Sachet placed in workstation through transfer lock
