1. METHODS OF SAMPLING AND TESTING PORTLAND 
CEMENT 
(A. S. T. M. standard method (-J) 2 serial designation C9-26, sections 16-57, inclusive) 
SAMPLING 
16. Tests may be made on individual or composite samples as may be ordered. 
Each test sample should weigh at least 4 pounds. 
17. (a i Individual sample. — If sampled in cars, one test sample shall be taken 
from each 50 barrels or fraction thereof.. If sampled in bins one sample shall 
represent each 2*00 barrels unless otherwise specified by the purchaser. 
( b ) Composite sample. — if sampled in cars, one sample shall be taken from 
1 sack in each 40 sacks (or 1 barrel in each 10 barrels) and combined to form 
one test sample. If sampled in bins or warehouses one test sample shall 
represent not more than 200 barrels unless otherwise specified by the purchaser. 
18. Cement may be sampled at the mill by any of the following methods 
that may be practicable, as specified : 
(a) From the conveyor delivering to the bin. — At least 4 pounds of cement 
shall be taken from approximately each 100 barrels passing over the conveyor. 
This may be secured by taking the entire test sample at a single operation, 
known as the grab method, or by combining several portions taken at regular 
intervals, known as the composite method. 
( b ) From filled bins by means of proper sampling tubes. — Tubes inserted verti- 
cally may be used for sampling cement to a maximum depth of 10 feet. Tubes 
inserted horizontally may be used where the construction of the bin permits. 
Sample shall be: taken from points well distributed over the face of the bin. 
(c) From filled bins at points of discharge. — Sufficient cement shall be drawn 
from the discharge openings to obtain samples representative of the cement 
contained in the bin, as determined by the appearance at the discharge open- 
ings of indicators placed on the surface of the cement directly above these 
openings before drawing of the cement is started. 
19. The sampling shall be done by or under the direction of a responsible 
representative of the purchaser. 
20. Samples preferably shall be shipped and stored in moisture-proof, air- 
tight containers. Samples shall be passed through a sieve having 20 meshes per 
linear inch in order to thoroughly mix the sample, break up lumps, and remove 
foreign materials. 
CHEMICAL ANALYSIS 
LOSS ON IGNITION 
21. One gram of cement shall be heated in a weighed covered platinum cruci- 
ble, of 20 to 25 cubic centimeter capacity, as follows, using either method (a) or 
( b ) as specified : 
Method (a) : The crucible shall be placed in a hole in an asbestos board, 
clamped horizontally so that about three-fifths of the crucible projects below. 
and blasted at a full red heat for 15 minutes with an inclined flame ; the loss 
in weight shall be checked by a second blasting for five minutes. Care shall be 
taken to wipe off particles of asbestos that may adhere to the crucible when 
withdrawn from the hole in the board. Greater neatness and shortening of the 
time of heating are secured by making a hole to fit the crucible in a circular 
disk of sheet platinum and placing this disk over a somewhat larger hole in an 
asbestos board. 
Method (&) : The crucible shall be placed in a muffle at any temperature be- 
tween 900° and 1,000° C. for 15 minutes and the loss in weight shall be checked 
by a second heating for 5 minutes. 
2 Italic figures in parentheses refer to literature cited, p. 129. 
