SOP - CALIBRATION OF BALANCES

1.0
PURPOSE:
To provide a written procedure for the steps to be followed while calibration of balances.
2.0
SCOPE:
Applicable to all balances except analytical balances.
3.0
RESPONSIBILITY:
All Department Heads
4.0
ACCOUNTABILITY :
Assistant Manager Manufacturing / Quality Assurance Manager
5.0
DEFINITIONS:
Calibration: The demonstration that an instrument or a device produces results within specified limits when compared to those produced by a reference standard (or) the standard, which is traceable to a national or International standard, over an appropriate range Of measurements.
6.0
PROCEDURE:
6.1
Check the cleanliness of the area.
6.2
Check that platform and exposed parts of the balance are clean and dry.
6.3
Check the level of the balance with the help of spirit level. Adjust level, if not leveled.
6.4
Switch on the main power supply of the balance.
6.5
Following parameters to be checked while performing calibration.
· Accuracy
· Linearity
· Precision
· Corner Load Test
FREQUENCY: Every 3 months (± 7 days)
Note: If balance is not calibrated within the time period, stop using the balance till
satisfactory calibration is done.
6.6
ACCURACY
6.6.1
Check the accuracy of the balance by using 5 standard stamped weights.
6.6.2
Place standard weight one by one in the ascending order in the center of the platform and record the observations in the balance calibration record.
6.6.3
Acceptance Criteria: Standard Weight ± 2 x Least Count
6.7
LINEARITY
Draw the linearity curve for the above readings and find out the correlation factor. Record the observations in the balance calibration record.(Limit: NLT 0.9999)
6.8
PRECISION
6.8.1
Check the Precision of the balance by using standard weight equivalent to 5 % of
Maximum capacity.
6.8.2
Repeat the procedure for 5 time and record the readings.
6.8.3
Repeat 6.8.1 to 6.8.2 using standard weight equivalent to 50 % of maximum
capacity.
6.8.4
Calculate % RSD for both the standard weights. Record the observations in the
Balance calibration record.
6.8.5
Acceptance Criteria :
% RSD NMT 0.5 %
6.9
CORNER LOAD TEST
6.9.1
Place standard weight equivalent to 30 % of maximum capacity in four corners and center of the balance and note down the readings in record. Calculate % RSD.
Record the observations in the balance calibration record.
6.9.2
Acceptance Criteria:
Deviation: Standard Weight ± 2 x Least Count
% RSD: NMT 0.5 %
6.10
If all the parameters fall with the acceptance criteria limit, affix the calibration tag (no. LBGN:003) on the balance.
6.11
If any of the observation is out of limit, correct and reset the balance.
6.12
After resetting, calibrate again all the parameters as mentioned in point 6.6 to 6.9
6.13
Switch off the balance at the end of day.
Note: No repairs should be made to any balance by anyone other than a qualified validation person from validation team.
7.0
REFERENCES:
Nil
8.0
ENCLOSURE:
8.1
Balance calibration record : XXXXXXX
9.0
ABBREVIATIONS:
9.1
NMT : Not More Than
9.2
RSD : Relative Standard deviation

10 comments:

Calibration said...

I actually enjoyed reading through this posting.Many thanks.Calibration

kaivan shah said...

hey nice information for us,thanks for sharing this information.Smart innovative and built-in safety features create new standards of security and user safety in analytical balance.

Analytical Balances manufacturers

Essae Chandran said...

Essae-Teraoka Ltd is one of the India's major suppliers of Analytical Balances and Scales. Analytical balances are accurate and actual equipment used to evaluate public. These days, Essae-Teraoka analytical balances provide a superior mixture of perfection, precision and value. From primary to complicated analytical with a weight of programs, Essae Analytical balances are the right choice for your business.
Analytical Balance

Ritesh said...

Dear thanks for the information, please provide the rational or guideline basis for this SOP, specially for the set Acceptance Criteria:
Standard Weight ± 2 x Least Count.

Please provide the details (weight consideration and acceptance criteria for repeatability, accuracy, uncertainty, eccentricity )for
1> 6kg X 0.5gm balance
2> 320 gm X 0.001gm

Ritesh said...

Dear thanks for the information, please provide the rational or guideline basis for this SOP, specially for the set Acceptance Criteria:
Standard Weight ± 2 x Least Count.

Please provide the details (weight consideration and acceptance criteria for repeatability, accuracy, uncertainty, eccentricity )for
1> 6kg X 0.5gm balance
2> 320 gm X 0.001gm

Abdul Vajith said...

I recently came accross your blog and have been reading along. I thought I would leave my first
comment. I dont know what to say except that I have enjoyed reading. Nice blog. I will keep
visiting this blog very often. I am an Glassware calibration lab in Chennai.
I feel great after reading this information. Please make update I will be regular rss to this site.
Mass Calibration Lab in Chennai
Weighing balance calibration lab in Chennai
nabl accredited calibration labs in chennai
Pipette calibration lab in Chennai

lee woo said...

Life is like riding a bicycle. To keep your balance, you must keep moving. See the link below for more info.


#balance
www.ufgop.org

chandaka narsimha said...

Thanks for the information....

Venkatesh Padmavathi said...

Dear
how to calculate the minimum and maximum values for weighing balances in pharma

sunil kumar said...

for minimum weight = Least count X 1000 e.g 0.0001gm is least count than minimum weigh on balance is 0.0001 X 1000 = 0.1g or 100mg.
For maximum weight 20% of maximum capcity e.g 110g max. capacity for balance you can weight up to 88gm