- PROCEDURE:
- Before operation of the Instrument connect to nitrogen cylinder with help vacuum tube and release nitrogen gas with low pressure to remove the moisture present inside the instrument.
- Continue purging operation for 1.0 hour.Operate the instrument as per the SOP.
- Recharge the Desiccant at about 200 0C for approximately 8.0 hours and check with colour indicator paper.
- Ensure the colour of indicator paper must be changed to dark blue.If the colour of the indicator paper is dull or are not changed to dark blue keep on drying at 2000C for few hours till to the colour of indicator paper changed to dark blue colour.
- Recharge and replace the Desiccant before calibration.
- Control of resolution absorbance:
- Record the spectrum of a polystyrene film approximately 35µm in thickness from 4000cm-1 to 450cm-1.
- The difference between the absorbance’s at the absorption minimum at 2870 cm –1 and the absorption maximum at 2849.5 cm-1 is greater than 0.33.
- The difference between the absorbance’s at the absorption minimum at 1589 cm–1 and the absorption maximum at 1583cm–1 is greater than 0.08.
- Verification of the wave-number scale.
- From the spectra obtained in the control of absorbance check the maximum at following wave numbers
Wave numbers (in cm –1 ) Tolerance (in cm –1 )
- 3060.0 (±1)
- 2849.5 (±1)
- 1942.9 (±1)
- 1601.2 (±1)
- 1583.0 (±1)
- 1154.5 (±1)
- 1028.3 (±1)
- Record the result in the format attached.
- Frequency: Half yearly.
- If the calibration is not within the specified standards, check the cleanliness of polystyrene film again and repeat the calibration.
- If the calibration is not proper then report the results to the departmental head for an appropriate action.
- ANNEXURES:
| ANNEXURE NO. | TITLE OF ANNEXURE |
| Annexure-I | Calibration record of Fourier Transform Infrared Spectrophotometer |
| Annexure-II | Desiccant maintenance Record for FTIR |
Annexure-I
CALIBRATION RECORD OF FOURIER TRANSFORM INFRARED SPECTROPHOTOMETER
Annexure-II
DESICCANT MAINTENANCE RECORD FOR FTIR
