sop for Rounding off numerical analytical results

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4 years ago

sop for Rounding off numerical analytical results

1.0 OBJECTIVE

1.1 To lay down a procedure for Rounding Off Numerical Analytical results to be followed in the Quality Control Department.

2.0 SCOPE :
2.1 This procedure is applicable to all the numeral results observed or calculated from experimental measurements in the Quality Control Department

3.0 RESPONSIBILITY :
3.1 Officer/Executive / Designee shall be responsible for rounding off the numerical analytical results.
3.2 Asst.Manager /Manager/Designee shall be responsible for ensuring that the rounding off the numerical analytical results are carried out as per laid down procedure.
3.3 AGM-QC to ensure compliance of this SOP.

4.0 ACCOUNTABILITY : Head-QC

5.0 PROCEDURE :
5.1 A reportable value is often a summary value for several individual determinations. It is the end result of a completed measurement method, as documented and is compared with the acceptance criteria.
5.2 Analytical results observed in the laboratory or calculated are compared with the stated limits to determine the conformance with the specifications.
5.3 The observed or calculated value usually contains more significant figures as there in the stated tolerance limit Therefore an observed or calculated result is rounded off to the number of places, which is in agreement with limit in the specification. For e.g., If specification limit is upto two decimal points (e.g. NLT 98.50 %), then results shall be reported upto two decimal points (e.g. 98.68 %).
5.4 For rounding off the results, consider only one digit in the decimal place to the right of the last place in the limit expression. If this digit is smaller than 5, it is eliminated and preceding digit remains unchanged. If this digit is 5 or greater than 5, it is eliminated and preceding digit is increased by 1.
5.5 Limits which are fixed numbers shall not be rounded off.
5.6 Rounding off shall not be done until the final calculations for the reportable value have been completed.
5.7 Illustration of rounding numerical values for comparison with requirements:

Compendial Requirement

Unrounded Value

Rounded Result

Conforms to Limit

Assay Limit > 98.0%

97.96 %

97.92 %

97.95 %

98.0%

97.9%

98.0%

Yes

Assay Limit > 98.50%

98.486 %

98.499 %

98.494 %

98.495%

98.49%

98.50%

98.49%

98.50%

Yes

Assay Limit < 101.5 %

101.55 %

101.46 %

101.45 %

101.6 %

101.5 %

Yes

Limit Test < 0.02%

0.025 %

0.015 %

0.027 %

0.03%

0.02%

0.03%

Yes

Limit Test < 3 ppm

3.5 ppm

3.4 ppm

2.5 ppm

4 ppm

3 ppm

Yes

5.8 Results shall be reported in 2 decimal places, if the acceptance criteria for respective test is 1% or less than 1%. However, if the acceptance limit is less than 0.1%, the results shall be reported with the decimal places as per conformance to the specified criteria/ in-house requirement.

6.0 ABBREVIATION :

Sr. No.	Abbreviation used	Full form of abbreviation used
1	QA	Quality Assurance
2	QC	Quality Control
3	AGM	Assistant General Manager
4	ppm	Parts per million
5	NLT	Not less than
6	Sr.	Senior
7	GM	General Manager
8	AGM	Assistant General Manager
9	%	Percentage
10	Ltd	Limited
11	>	Greater than or equal to
12	<	Less than or equal to
13	SOP	Standard Operating Procedure
14	No.	Number