The calibration specifications and procedures for the Vertical Combustion Tester (VCT) can vary according to different standards and organisational requirements. The following is a rough guide to calibration specifications for reference:

1. Preparation:

   - Check the calibration equipment: Ensure that the calibration equipment used complies with the relevant international or industry standards and is in proper working order. The calibration equipment should be sufficiently accurate and reliable.

   - Check Instrumentation: Ensure that all instrumentation (e.g. thermometers, altimeters, time meters, etc.) of the Vertical Combustion Tester is in proper working order and that the calibration expiration date has not been exceeded.

2. Temperature Calibration:

   - Use a standard thermometer to calibrate the temperature measurement system of the vertical combustion tester. Place a standard thermometer in the temperature measurement position of the vertical combustion tester and compare the readings.

   - Make adjustments based on differences between the readings of the standard thermometer and the vertical combustion tester to ensure that the accuracy meets specification requirements.

3. Height Calibration:

   - Calibrate the height measurement system of the vertical combustion tester using a standard altimeter. Place a standard altimeter in the height measurement position of the vertical combustion tester and compare the readings.

   - Adjustments are made based on the difference between the readings of the standard altimeter and the vertical combustion tester to ensure accuracy in accordance with code requirements.

4. Time Calibration:

   - Calibrate the time measurement system of the vertical combustion tester using a standard timer. Start both the vertical combustion tester's timer and the standard timer and compare readings.

   - Adjustments are made based on the difference between the Standard Timer and Vertical Flame Tester readings to ensure accuracy in accordance with code requirements.

5. Flame Height Calibration:

   - Calibrate the flame height measurement system of the vertical combustion tester using a standard flame height measurement tool or instrument. Adjustments are made based on the readings of the standard tool or instrument to ensure that the accuracy meets the requirements of the specification.

6. Data Recording and Verification:

   - During the calibration process, the readings and adjustments of the calibration equipment and vertical combustion tester are recorded in detail for future reference.

   - After completing the calibration, test the Vertical Combustion Tester with a standard sample and compare it with the previously recorded test results to ensure the accuracy and stability of the calibration.

Please note that the above is only a general calibration sequence and step-by-step guide and does not take into account specific standards and organisational requirements. Specific calibration specifications may be adjusted according to actual conditions and standard requirements. Always refer to the relevant standards and specifications and follow the user manuals and instructions provided by the manufacturer when performing calibration. If calibration is required or if you have any questions, it is recommended that you consult a professional calibration laboratory or technician for assistance.