*Appendix IV*

* *__USING TOLERANCE LEVELS__* *

When making comparison of the information given on label with the
results reported by the laboratory, note that the percentages of germination
and pure seed given on label need not necessarily be equal to or higher than
the results reported by the laboratory on the basis of the Inspector’s sample
but can be lower than the results reported up to a certain level called the
“tolerance level”. If the percentage of germination or pure seed given on label
is equal to or less than what is reported by the laboratory but is still
conforming to the minimum limits prescribed, labelling is satisfactory. If the
percentage of germination or pure seed on the label is higher than reported by
the laboratory, verify whether or not the difference between the details on the
label and he results from the laboratory is within the tolerance. If this
indifference is within the tolerance, labelling is satisfactory.

To verify whether or not the
difference between the details on the label and the results from the laboratory
is within tolerance or whether it is large enough to consider labelling as
faulty, use the prescribed tolerance tables. Six types of tolerance tables as
in Table II to Table VII are applicable for different situation as below:

**Table II** To be
used when comparing laboratory’s results on pure seed, inert matter, other crop
seed and weed seed, with the details on label. To use this table both the
laboratory’s results and the details on label should be in percentage by
weight.

**Table III** To be
used when comparing laboratory’s results on foreign seed count viz. other crop
seed and weed seed with the details on label. To use this table both the
laboratory’s results and the details on label should be in number per unit
weight.

**Table IV** To be
used when comparing laboratory’s results on germination with the details on
label.

**Table V** To be
used when comparing laboratory’s results on pure seed, inert matter, other crop
seed and weed seed with the minimum standards prescribed. To use this table
both the laboratory’s results as well as the minimum standards prescribed
should be in percentage by weight.

**Table VI** To be
used when comparing laboratory’s results on foreign seed count viz. other crop
seed and weed seed with the minimum standards prescribed. To use this table
both the laboratory’s results as well as the minimum standards prescribed
should be in number per unit weight.

**Table VII** To be
used when comparing laboratory’s results on germination with the minimum
standards prescribed.

Use Tables II to IV in comparing laboratory’s results with the
details given on label. Use Tables V to VII in comparing laboratory’s results
with the minimum standards prescribed. Comparison of the laboratory’s results
with the minimum standards for verification of correctness of labelling may be
necessary for seed packed to a net weight of less than 250 grams when detailed
information on label is not required. Note that the use of tolerance tables is
required only when the laboratory’s results show lower germination or pure seed
content or higher inert matter, other crop seed or weed seed content than what
is given on the label.

The following steps are involved in verifying whether or not the
difference between the laboratory’s results and the details given on label is
within the tolerance level:

For purity components by weight:

a.
calculate the average of the two viz. Laboratory’s result and the percentage given
on label. The average should be in two decimals.

b.
fit in the average in the suitable class interval in column A
or B of Table II; against this interval read the tolerance level in column C or
D.

c.
if the difference between the two viz. laboratory’s result and
information on label is equal to or less than the tolerance level in column C
or D, then the difference is permissible and labelling is satisfactory. If the
difference is more than the tolerance
level, labelling is wrong and requires further action.

For
foreign seed count by number per unit weight:

a.
follow the same procedure as above but use Table III.

For
germination:

a.
follow the same procedure as above but use Table IV.

The following steps are involved in verifying whether or not the difference between the laboratory’s results and the minimum standards prescribed is within the tolerance level:

For purity components by weight:

a.
Fit in the minimum standard prescribed in the suitable class
interval in column A or B in Table V and against this class interval read the
tolerance level in column C or D.

b.
if the difference between the standard prescribed and the
laboratory’s results is equal to or lower than the tolerance level labelling
is satisfactory.

For
foreign seed count by number per unit weight:

a.
follow the same procedure as above but use Table VI.

For
germination:

a.
follow the same procedure as above but use Table VII.

Each
of the above six situations is illustrated below:

a. Comparison of laboratory’s result with label:

i. for any purity component in percentage by weight:

( e. g.) Pure seed of what i.e. non-chaffy.

Laboratory’s result : 97.0%

On label : 98.7%

Average : __(97.0 + 98.7)__ _{=} __195.7
__
2
2

: 97.85%

Class interval in

column A of Table II : 97.75 – 97.99

Tolerance level in

column C of Table II : .88

Difference between

laboratory’s result and

label information : (98.70 – 97.00) = 1.70

Conclusion: Since the difference between the laboratory’s result and information on label is higher than the tolerance level, labelling is wrong.

ii. for foreign seed component by number per unit weight:

(e.g.) Weed seed

Laboratory’s result : 77/Kg.

On label : 73/Kg.

Average : __(77 + 73)__ _{=} __150__ _{=} 75

2
2

Class interval in

Column A of Table III : 75

Tolerance level in

column B of Table III : 97

Difference between

laboratory’s result and

label information : 77-73
= 4

Conclusion: Since the difference
between the laboratory’s result and information on label is less than the
tolerance level, labelling is satisfactory.

iii. for germination:

Number of tests conducted : 2

Laboratory’s result : 89%

On label : 91%

Average :
__(89 + 91)__ _{=} __180__
_{=90%}

3 2

Class
interval in column A

of Table IV
: 90

Tolerance
level in column E

of Table IV
:
4

Difference
between

laboratory’s
result and

label
information
: (91- 89) = 2

Conclusion: Since the difference between the laboratory’s result and the information on label is less than the tolerance, labelling is satisfactory.

b. Comparison of laboratory’s result with the minimum standard prescribed :

i. for any purity component in percentage by weight :

(e.g.) Inert matter in bhindi (e.g.) non-chaffy.

Laboratory’s result : 1.48%

Standard : 1.00%

Class interval in column B of Table V: 1.00 – 1.24

Tolerance level in column C

of Table V : .48

Difference between the standard and

the laboratory’s result : (1.48 – 1.00) = .48

Conclusion: Since the difference between the standard and laboratory’s result is equal to the tolerance level, labelling is satisfactory.

ii. for foreign seed count by number per unit weight :

(e.g.) Other crop seed

Laboratory’s result : 27/Kg.

Standard : 5/Kg.

Class interval in column A

of Table VI : 5

Tolerance level in column B

of Table VI : 10

Difference between the Laboratory’s

result and standard : (27 – 5) = 22

Conclusion: Since the difference between laboratory’s result and standard is more than the tolerance level labelling is wrong and needs to be redone or alternatively re-grading needs to be done.

iii. For germination :

Number of replicates : 4 with 100 seeds each

Number of seeds : 400

Laboratory’s result : 77%

Standard : 80%

Class interval in column A

of Table VII : 80

Tolerance level in column C

of Table VII : 5

Difference between the laboratory’s

result and the standard : (80 – 77) = 3

Conclusion: Since the difference between the laboratory’s result and the

Standard is less
than the tolerance level, labelling is

satisfactory.

Only when the label is showing germination or pure seed more than what is reported by the laboratory or inert matter, other crop seed or weed seed less than what is reported by the laboratory apply the tolerance levels to verify whether or not the difference between the laboratory’s result and the detail on the label is within acceptable limits. Labelling is satisfactory if the difference is within the tolerance level. It is unsatisfactory and calls for further action as required if the difference is not within the tolerance level.