Instrument Operation of Antibiotic Zone reader

1.0 Purpose :
The purpose of this procedure is to describe the method of operation of Antibiotic zone reader.
2.0 Scope :
This procedure applicable to Antibiotic zone reader used in QC department (microbiology department)
3.0 Responsibility :
Manager QC & Microbiologist QC.
4.0 Procedure :
Check that the instrument is clean and kept in proper position.
Connect the power cable to the mains and switch ‘ON’.
Switch ‘ON’ the mains in the instrument.
Ensure that the zero of the main scale coincides with zero of the main scale coincides with zero in the vernier scale.
Place the petridish in such a way that the lower edge of the zone
coincides with the mark line on the prism and in the centre of the magnifier.
Rotate the left side knob anticlockwise till the upper edge of the zone coincides with the mark line on the prism.
Note down the reading in mm with respect to the main scale and vernier.
Rotate the stage anticlockwise using the handle provided at the left hand side and bring it to the zero position.
After completion of work switch ‘OFF’ the mains.
NOTE: Always ensure that the stage is in zero position of the scales before taking reading.