Testing of industrial products - Aggregates for construction

Precision values obtained from the cross-testing experiments on the micro-Deval test

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Note. For all the tables here, "stragglers" have been included in the calculations, and "outliers" have been excluded.

Table 1. Repeatability and reproducibility
for the European cross-testing experiment.
MDE units (percentages passing the test sieve)
		Level 1	Level 2	Level 3
Number of laboratories included	N	17	17	15
Average	X	6.4	11.7	25.6
Repeatability standard deviation	S_r1	0.291	0.385	0.335
Reproducibility standard deviation	S_R1	0.344	0.890	1.086
Critical range	W_c	0.9	1.3	1.3
Repeatability value	r₁	0.8	1.1	0.9
Reproducibility value	R₁	1.0	2.5	3.0

Table 2. Functional relations
for the European cross-testing experiment.
MDE units (percentages passing the test sieve)
	Functional relations
Repeatability standard deviation	S_r1 = 0.319 + 0.001 X
Reproducibility standard deviation	S_R1 = 0.093 + 0.049 X
Repeatability value	r₁ = 0.893 + 0.003 X
Reproducibility value	R₁ = 0.260 + 0.137 X

Table 3. Repeatability and reproducibility standard deviations
expressed as coefficients of variation
for the European cross-testing experiment.
		Level 1	Level 2	Level 3
Repeatability coefficient of variation	C_r1	4.5	3.3	1.3
Reproducibility coefficient of variation	C_R1	5.4	7.6	4.2

Table 4. Sensitivity ratios
for the European cross-testing experiment.
	Level 2 - Level 1	Level 3 - Level 2	Level 3 - Level 1
Repeatability	11.0	27.2	43.3
Reproducibility	5.6	9.9	16.9

Table 5. Repeatability and reproducibility
for the French cross-testing experiment.
MDE units (percentages passing the test sieve)
		Level 1	Level 2	Level 3
Number of laboratories included	N	35	36	34
Average	X	6.5	11.8	25.8
Repeatability standard deviation	S_r1	0.230	0.457	0.339
Reproducibility standard deviation	S_R1	0.381	0.820	1.289
Critical range	W_c	0.9	1.2	1.3
Repeatability value	r₁	0.6	1.3	1.0
Reproducibility value	R₁	1.1	2.3	3.6

Table 6. Functional relations
for the French cross-testing experiment.
MDE units (percentages passing the test sieve)
	Functional relations
Repeatability standard deviation	S_r1 = 0.285 + 0.004 X
Reproducibility standard deviation	S_R1 = 0.069 + 0.053 X
Repeatability value	r₁ = 0.798 + 0.011 X
Reproducibility value	R₁ = 0.193 + 0.148 X

Table 7. Repeatability and reproducibility standard deviations
expressed as coefficients of variation
for the French cross-testing experiment.
		Level 1	Level 2	Level 3
Repeatability coefficient of variation	C_r1	3.5	3.9	1.3
Reproducibility coefficient of variation	C_R1	5.9	6.9	5.0

Table 8. Sensitivity ratios
for the French cross-testing experiment.
	Level 2 - Level 1	Level 3 - Level 2	Level 3 - Level 1
Repeatability	10.4	24.6	47.1
Reproducibility	5.9	9.2	14.4