Parr Instrument 6100 - Manual (Page 56)

C
Standardization
P a r r I n s t r u m e n t C o m p a n y 54
Table C-2
Calorimeter Control Limit Values in cal/g When Benzoic Acid is Used as a Test Sample
Accepted heat of combustion taken as 6318 cal/g.
Instrument precision 0.20%.
Control limits based on 99% confidence (3 sigma) values.
Values are in cal/g.
NUMBER OF
OBSERVATIONS
IN A GROUP
UCL FOR THE RANGE
(HIGH – LOW) WITHIN
THE GROUP
UCL FOR THE
RSD WITHIN THE
GROUP
MAXIMUM PERMISSIBLE DEVIATION
OF THE GROUP MEAN FROM THE
ACCEPTED VALUE OR GRAND MEAN
1 37.9
2 46.6 0.521% 26.8
3 55.1 0.455% 21.9
4 59.4 0.418% 19.0
5 62.1 0.393% 17.0
6 64.2 0.375% 15.5
7 65.7 0.361% 14.3
8 67.1 0.350% 13.4
9 68.2 0.341% 12.6
10 69.1 0.334% 12.0
11 69.9 0.327% 11.4
12 70.7 0.322% 10.9
13 71.3 0.317% 10.5
14 72.0 0.313% 10.1
15 72.5 0.309% 9.8
16 73.1 0.305% 9.5
17 73.5 0.302% 9.2
18 74.0 0.299% 8.9
19 74.4 0.297% 8.7
20 74.8 0.294% 8.5
21 75.2 0.292% 8.3
22 75.6 0.290% 8.1
23 75.9 0.288% 7.9
24 76.2 0.286% 7.7
25 76.5 0.284% 7.6