THE BROWN-DUVEL MOISTURE TESTER 
29 
Table 5. — Damaged or incorrectly placed icire gauzes cause errors im moisture 
test results in testing icheat 
[Wire gauzes that are damaged or incorrectly placed in the compartments of the moisture tester affect the 
heating time of tests and cause variations in moisture results] 
Condition of wire gauze 
Compartment No. 
Good and cor- 
rectly placed 
(check) 
Good, but flame 
striking edge of 
asbestos center 
Damaged (asbes- 
tos burned off and 
holes in gauze) 
Good and cor- 
rectly placed 
(check) 
Heating 
time 
Mois- 
ture 
Heating 
time 
Mois- 
ture 
Heating 
time 
Mois- 
ture 
Heating 
time 
Mois- 
ture 
1 
Minutes 
my 2 
18 
18M 
1834 
18M 
18 
Per cent 
13.1 
13.3 
13.2 
13.4 
13.3 
13.1 
Minutes 
1734 
17 
18M 
1734 
1534 
16K 
Per cent 
13.3 
13.4 
13.6 
13.7 
12.9 
13.1 
Minutes 
■ Yl\i 
\m 
17H 
15 
15 
17 
Per cent 
13.3 
13.6 
13.5 
13.7 
13.1 
13.2 
Minutes 
18 
1834 
18 
Per cent 
13.0 
2 
13.2 
3 
13.2 
4 
18M 13. 3 
1834] 13. 2 
6 
18 | 13. 1 
1SH 
34 
13.2 
0.3 
17 
2M 
-1M 
13.3 
0.8 
+0.1 
1634 
2% 
-1% 
13.4 
0.6 
+0.2 
18J4 13.2 
34 1 0.3 
VARIATIONS IN HEATING TIME CAUSED BY VARIATIONS IN 
THERMOMETER-BULB IMMERSION 
Data in Table 6, illustrated in Figure 22, show that a deeper 
immersion than the correct depth of four-fifths immersion of the 
mercury bulb of the thermometer in the oil will cause a faster 
heating time and a lower percentage of moisture, and that a 
shallower depth of immersion will cause a slower heating time and 
a higher percentage of moisture. 
To insure correct moisture test results from the standpoint of this 
factor, the depth of immersion of the mercury bulb of each ther- 
mometer should be carefully noted and adjusted to the correct four- 
fifths immersion for each test. 
Table 6. — Variations in the depth of immersion in oil of the thermometer 
bulb will affect the heating time and cause errors in the moisture-test 
result 
Bulb immersion 
Average 
Maximum 
Minimum 
Range 
Average varia- 
tion from cor- 
rect (four-fifths) 
immersion 
Heat- 
ing 
time 
Mois- 
ture 
Heat- 
ing 
time 
Mois- 
ture 
Heat- 
ing 
time 
Mois- 
ture 
Heat- 
ing 
time 
Mois- 
ture 
Heat- 
ing 
time 
Mois- 
ture 
Bulb touching sur- 
surface 
Min- 
utes 
19 
17M 
16 3 ^ 
16H 
16 
Per 
cent 
10.5 
10.3 
10.2 
10.1 
10.0 
Min- 
utes 
1934 
Wi 
17 
16M 
1634 
Per 
cent 
10.6 
10.4 
10.3 
10.2 
10.2 
Min- 
utes 
1834 
17 
1634 
Per 
cent 
10.4 
10.3 
10.0 
Min- 
utes 
1 
u 
34 
% 
H 
Per 
cent 
0.2 
0.1 
0.3 
0.2 
0.3 
Min- 
utes 
2% 
1 
3'2 
Per 
cent 
+0.4 
Bulb one-fifth im- 
mersed 
+0.2 
Bulb one-half im- 
mersed __ 
+0.1 
Bulb four-fifths im- 
16 10.0 
Bulb totally im- 
mersed 
15J4 
9.9 
-H 
-0.1 
1 Correct position. 
