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IS0
I NT ERN AT1 ON A L O R G A N IZ AT1 O N FOR STAN DA R D I Z AT1 O N
IS0 RECOMMENDATION
R 287
PAPER
METHOD FOR THE DETERMINATION
OF MOISTURE CONTENT OF PAPER
(OVEN-DRYING METHOD)
1st ED IT I O N
January 1963
COPYRIGHT RESERVED
The copyright of IS0 Recommendations and IS0 Standards
belongs to IS0 Member Bodies. Reproduction of these
documents, in any country, may be authorized therefore only
by the national standards organization of that country, being
a member of ISO.
For each individual country the only valid standard is the national standard of that country.
Printed in Switzerland
Also issued in French and Russian. Copies to be obtained through the national standards organizations.
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BRIEF HISTORY
The IS0 Recommendation R 287, Method for the Determination of Moisture Content of
Paper (Oven-Drying Method), was drawn up by Technical Committee ISO/TC 6, Paper, the
Secretariat of which is held by the Association Française de Normalisation (AFNOR).
Work on this question by the Technical Committee began in 1958 and led, in the same year,
to the adoption of a Draft IS0 Recommendation.
In October 1960, this Draft IS0 Recommendation (No. 404) was circulated to all the IS0
Member Bodies for enquiry. It was approved by the following Member Bodies :
Australia India Poland
Belgium Iran Republic of South Africa
Chile Ireland
Romania
Czechoslovakia Israel Spain
Denmark Italy Turkey
France Japan United Kingdom
Germany Mexico U. S. S. R.
Greece Norway Yugoslavia
Four Member Bodies opposed the approval of the Draft:
Finland, Netherlands, New Zealand, Sweden.
The Draft IS0 Recommendation was then submitted by correspondence to the IS0
Council, which decided, in January 1963, to accept it as an IS0 RECOMMENDATION.
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ISO/R 287 - 1963 (E)
IS0 Recommendation R 287 January 1963
PAPER
METHOD FOR THE DETERMINATION
OF MOISTURE CONTENT OF PAPER
(OVEN-DRYING METHOD)
1. OBJECT AND SCOPE
This IS0 Recommendation describes a method for the testing of paper to determine its moisture
content at the time of sampling.
The method applies to papers that do not contain any appreciable quantity of materials, other
than water, which will escape at the temperatures specified for the test.
It applies in general only to paper of a substance below 250 g/mz.
2. TERMINOLOGY
2.1 Moisture content. - Amount of water in a paper. In practice, loss in mass of a test piece
when dried to constant mass under the test conditions standardized. It is expressed as a per-
centage of the initial mass of paper as sampled.
Moisture content on an oven-dry basis. - Loss in mass of a test piece, after drying to constant
2.2
mass under the test conditions standardized, and expressed as a percentage of the constant
mass so obtained.
2.3 Constant mass.- Mass reached by a test piece of paper after drying at the specified temper-
ature until the difference between two successive weighings does not exceed 0.1 per cent
of the initial mass of the test piece.
3. PRINCIPLE
Weigh the test piece at the time of sampling, and again after drying to constant mass.
4. APPARATUS
4.1 Balance
The balance should have an accuracy of at least 0.05 per cent of the mass to be weighed.
4.2 Sample containers
Containers for the transporting and weighing of test pieces should be water-vapour proof
and made from a light-weight material not subject to change under the conditions of test.
4.3 Oven
The oven should be capable of maintaining the air temperature between 102 "C and 105 "C
and should be suitably ventilated.
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ISO/R 287 - 1963 (E)
5. PRELIMINARIES
5.1 Before commencing to take samples, clean and dry containers in sufficient quantity are
numbered, weighed and kept closed until the sample is about to be taken. Each container
should be weighed after having been allowed to attain temperature equilibrium with the
atmosphere.
5.2 If the atmosphere at the place of sampling is warm and damp, precautions should be taken
to prevent errors due to condensation either in or on the container.
5.3 Special precautions should be taken in handling the sheets, to avoid contamination and
any gain or loss of moisture. In particular, it is recommended that rubber gloves should
be worn. To avoid moisture changes due to atmospheric exposure, it is important also to
enclose all samples in their containers immediately after taking them.
6. SAMPLING
6.1 Selection of units
The units to be sampled should be selected in accordance with IS0 Reconimendation R 186,
Method of Sampling Paper for Testing, i.e. as follows:
Number of units
Size of lot (n) Method of selection
selected
I
~
-
from 1 to 5 units all
at random
from 6 to 99 units 5
n*
from 100 to 399 units at random
20
400 or more units 20 at random
* Any remainder of less than 20 units should be ignored.
Selection, preparation and weighing of test pieces
6.2
WHEN THE UNIT IS THE REAM OR PARCEL
6.2.1
(a) Determination of the average value ofmoisture content in the lot
At least four consecutive sheets should be taken from the centre of each ream or
parcel; they should be quickly folded or cut, and then enclosed in one of the con-
tainers. These test pieces should weigh at least 50 grammes. The containers and
contents should be weighed and the mass of the test piece calculated.
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ISO/R 287 - 1963 (E)
(b) Determination of the variation in moisture content between the centre and edges of sheets
From the centre of each ream or parcel, a number of consecutive sheets should be
taken, sufficient to give test pieces of at least 50 grammes mass after cutting strips
in the following manner: from these sheets, four strips 50 mm to 75 mm wide should be
cut in the cross direction, one from each edge and two near the centre. The two
strips taken near the centre should h
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