ISO/R 91:1970

II I
/
IS0
I N T ER N AT I O N A L O R G A N I Z AT I O N F O R S TA N DARD IZATl O N
ADDENDUM I
TO
IS0
RECOMMENDATION
R 91 -1970
PETROLEUM MEASUREMENT TABLES -
TABLES BASED ON A REFERENCE TEMPERATURE OF 20 "C
1st EDITION
July 1975

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,
BRIEF HISTORY
Addendum 1 to IS0 Recommendation R91-1970 was drawn up by Technical Committee
ISOlTC 28, Perroleurn products, and circulated to the Member Bodies in February 1974.
It has been approved by the Member Bodies of the following countries :
Australia Romania
Hungary
Austria India South Africa. Rep. of
Belgium
Israel Spain
Thailand
Czechoslovakia Japan
Egypt, Arab Rep. of Mexico Turkey
France Net herlands United Kingdom
Germany Poland U.S.S.R.
The Member Bodies of the following countries expressed disapproval of the document
on technical grounds :
Canada
U.S.A.
e' i
'W
Q International Organization for Standardization, 1975 O
Printed in Switzerland

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-3-
CONTENTS
Page
................................
1Scope 5
2 Field of application
............................ 5
3 General. . 5
4Tables . 6
............ 7
A Reduction of observed density (kg/l) to density (kg/l) at 20 "C
35
.........
B Factors for reduction ofvolume to 20 "C against density (kg/l) at 20 "C
C Kilograms (apparent mass as determined by weighing in air) per litre at 20 "C and litres at
20 "C per long ton (apparent mass as determined by weighing in air) against density (kg/l)
at20"C. . 63 f.
D Litres at 20 "C per litre at 15 OC; per gallon (UK), per gallon (US), per barrel (US) at 60 OF;
against density (kg/l) at 20 OC . 69
E Conversion of density (kg/l) at 15 OC, relative density 60/60 OF, and API gravity to density
(kg/l) at 20 OC . 71
$'
F Litres at 20 "C per litre at 15 "C against density (kg/l) at 15 "C; litres at 20 "C per gallon (UK)
and per barrel (US) at 60 "F against relative density 60/60 OF; litres at 20 "C per gallon (US)
at 60 OF against API gravity . 85

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1
-5- ISO/K 91-1970/Add.l-l975 (E)
Addendum 1 - May 1975 - to IS0 Recommendation R 91 -1970
PETROLEUM MEASUREMENT TABLES
This Addendum to IS0 Recommendation R 91-1970 comprises petroleum measurement tables based on a
reference temperature of 20 OC. These tables, known generally as "20 OC Tables", are for use in the calculation
of quantities of crude petroleum and petroleum products at a standard temperature of 20 "C. Tables are provided
over normal operating ranges for the reduction of density and volume to the standard state, and for the calcu-
lation of mass-volume relationships. Results obtained by the use of these tables give comparable figures to those
derived for the standard temperatures of 60 "F and 15 "C by the use of factors from the tables referred to in
ISO/R 91-1970.
2 FIELD OF APPLICATION
2.1 These tables are intended for application to crude petroleum regardless of source and to all normally liquid
petroleum products derived therefrom regardless of the method of manufacture. In the preparation of
these tables for density values above 0,600, it has been assumed for the purpose, of standardization that
all crude petroleum and petroleum products having similar densities have uniform coefficients of
expansion.
In the case of certain crudes and the liquid products derived from them, minor discrepancies may arise
in the calculation of oil quantities.
22 The tables cover a density range of 0,500 to 1,100. *'
2.3
The tables which involve reduction of density to standard temperature assume that the measurement
has been made by means of a glass hydrometer calibrated in kg/l (g/ml) at 20 "C and accordingly a
correction for the thermal expansion of hydrometer glass has been incorporated which is in accord with
the recommended value given in ISO/R 1768, Glass hydrometers - Conventional value for the thermal
expansion coefficient (for use in the preparation of measurement tables for liquids).
3 GENERAL
3.1 Definition of terms
Constants and factors used in the computation of the tables contained in this addendum are identical,
wherever possible, with those employed in the tables referred to in ISO/R 91-1970. A review of
significant terms is given here.
The implied definition of "density" as-used in these tables is mass per unit volume at 20 OC, expressed in
kilograms per litre (kg/l).

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-6- ISO/R 91-1970/Add.l-1975 (
Relative densityl) 60/60 OF is the ratio of the mass of a volume of a petroleum product at 60 "F to
the mass of the same volume of water at 60 OF.
MI gravity is based on the formula
141,s
"API = - 131,s
Relative density 60/60 OF
3.2 Comparison of mas determined by calculation from volume and density and the quantity measured
by direct weighing in au
oil is calculated by the multiplication of the determined density by the volume
When the quantity of
in litres at the same temperature, the result is a mass. In order to compare such a result with the
corresponding values obtained by weighing in air in the U.S.A. system or the British system of measuring,
it must be corrected for the effect of the buoyancy of air on the liquid being weighed and on the brass
weightsz). This correction has been incorporated into the values in these tables.
3.3
Significant figures in reporting bulk quantities of oil
The number of significant figures to be used in the reporting of bulk oil quantities should not be greater
than the minimum necessary to express adequately a particular quantity with due regard to the accuracy
in measurement and the accuracy desired for use. No rigid rules for significant figures can be laid down
which will cover every eventuality; however, the foliowing is given as guidance :
All values should be rounded off to five significant figures except :
where a larger number of digits is necessary to satisfy fiscal, customs or other authorities'
a)
requirements;
where a quantity exceeds a five-digit number, in which case the figure should be rounded off to the
b)
nearest digit;
where units of the order of size of kilograms, litres, pounds or gallons are used, in which case the
c)
values should be reported to the nearest whole kilogram, litre, pound or gallon;
where units of the order of size of barrels, tonnes or long tons are used, in which case the values
d)
should be reported to not more than two decimal places.
Examples :
528 kg; 410,72 tonnes; 122 Ib; 1 060,8 long tons; 116 litres, 75 O12 gal (UK); 4 023 486 gal (US);
116 223 barrels (US).
NOTE - This recommendation applies to the final reported quantity only. Intermediate values in the course of
e'
calculation should retain sufficient figures to ensure the greatest possible arithmetical accuracy.
4 TABLES
'.
In the following tables, the constants and factors used in the computation were identical, wherever possible,
with those employed in the computation of the tables referred to in ISO/R 91-1970.
.
1) This term is now used in lieu of "specific gravity".
2) It is assumed that the weights are made of brass of density 0,814 3 g/ml at O 'C.

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-7- ISO/R 9 1-1970/Add.l-1975 (E
TABLE A
Reduction of observed density (kg/l)
to density (kg/l) at 20 "C
This table gives values of density in kilograms per litre at 20 "C corresponding to densities observed with a glass hydro-
meter at temperatures other than 20 "C.
The expression "observed hydrometer reading" appears in the table heading, since this hydrometer reading differs
slightly from the true density at the observed temperatiire owing to the expansion or contraction of the glass hydrometer
when its temperature differs from its calibration tempeiature of 20 "C. Accordingly, a correction for hydrometer glass
expansion was included along with the expansion of petroleum products in the preparation of this table. For this reason,
the table is not to be used for densities observed by any other means.
This table must be entered only with densities measured1 with a soda-time glass hydrometer calibrated at 20 "C.
NOTE - Where a pressure hydrometer has been used to obtain ,i density for L.P.G. below 0,650 density it should be noted that the
coefficient of expansion may be different from that of soda-lime glass. However, since the factors in this range are given only to three
'significant figures any difference will be negligible and may be neglected.
(Attention is drawn in the following example to the change fiom three to four significant figures in the factors.)
Example :
If the density (kg/l) of an oil is 0,6448 at 27,5 OC, what is its density (kg/l) at 20 "C?
Enter the table with the column headed 0,640 under "observed hydrometer reading"
and note that against "Obs. temp. "C" 27,5 the "corresponding density
20 OC" is . . . . . . . . . . . . . . . . . . . . . . . . . , . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0,647 kg/l
Likewise, note that for a density of 0,650 at 27,5 "C the corresponding value
at 20 "C is 0,6569 which rounded off to three significant figures is. . . . . . . , . . . . . . . . 0,657 kg/l
Thus, for an increase of 0,010 in the observed value at 27,5 OC there is an
increase of 0,010 at 20 "C. Therefore, by simple proporlion, for a change in
density at 27,5 "C from 0,640 to 0,6448 there is a change in the density at
t'
20 "C by [(O,OlO/O,OlO) X (+ 0,0048)] or + 0,005 kg/l
Then, the density at 20 "C corresponding to the density of 0,6448 at 27,5 "C
0,651, kg/l
is [0,647 -I- 0,005] or. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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-8- ISO/R 91-1970/Add.I-1975 (E)
TABLE A
0,500 to 0,590
Reduction of density to 20 C
-25 to 0.C
Observed hydrometer reading
Obs.
temp.
0,500 0,510 0,520 0,530 0,540 0,550 0,560 0,570 0,580 0,590
OC
I
Correspondins density (kg/ll 20 "C
-
- 25,o
O, 500 0,512
0,524 0,536
- E4,5
0,501 0,513
0,525 0,537
- 24,o
0,501 0,513 0,526 0,537
- i3,5
O, 502 0,514
0,526 0,538
- 23,O !
O, 503 0,515
0,527 0,539
- 22,5
O, 504 0,516 0,527 0,539
- 22,o
O, 504 0,516 0,528 0,540
I
- 21,5
O, 505 0,517
0,529 0,540
- 21,o
O, 506 0,518 0,529 0,541
- 20,5
O, 506 0,518 0,530 0,542
- 20,o
O, 495 O, 507 0,519 0,531 0,542
- 19,5
O, 496 O, 508 O, 520
0,531 0,543
- 19,0
O, 497 O, 508 O, 520
0,532 0,544
- 18,5
O, 497 O, 509 0,521 0,533 0,544
- 18,O
O, 498 0,510 O, 522 0,533 0,545
- 17,5
O, 499 0,510 O, 522 0,534 0,546
- 17,0 O, 499 I
0,511 O, 523 0,535 0,546
- 16,5
O, 500 0,512 O, 524 0,535 0,547
- 16,O
O, 501 0,513 O, 524 0,536 0,547
- 15,5
O, 501 0,513
O, 525 0,537 0,548
- 15,0
O, 502 0,514 O, 526 0,537 0,549
- 14,5
O, 503 0,515 O, 526 0,538 0,549
- 14,0
O, 504 0,515
O, 527 0,539 0,550
- 13,5
O, 504 0,516 O, 528 0,539 0,551
- 13,0
O, 505 0,517 O, 528
0,540 0,551
- 12,5 O, 506 0,517
O, 529 0,540 0,552
- 12,o
O, 495 O, 507 0,518 O, 530 0,541 0,553
- 11,5
O, 496 O, 507 0,519 O, 530
0,542 0,553
- 11,o
O, 496 O, 50% O, 531
0,520 0,542 0,554
!
- 10,5 O, 509
O, 497 O, 520 O, 532 0,543 0,554
; *'
- 10,o O, 498 O, 509
O, 521 O, 532 0,544 0,555
- 9,5 O, 499 0,510
O, 522 O, 533 0,544 0,556
- 9,0
O, 499 0,511 O, 522 O, 534
0,545 0,556
- 8,5 O, 500 0,512 O, 523 O, 534 0,546 0,557
- 8,O O, 501 0,512 0,524 O, 535
0,546 0,558
- 7,5 O, 502 0,513 O, 524 O, 536 0,547 0,558
- 7,o O, 502 0,514 O, 525 O, 536 0,548 0,559
- 6,5 O, 503 0,514 O, 526 O, 537 0,548 0,559
- 6,O O, 504 O, 51 5 O, 526 O, 538 0,549 0,560
- 5,5 O, 504 O, 51 6
O, 527 O, 538 0,549 0,561
O, 505 O, 51 7
- 5,o O, 528 O, 539 0,550 0,561
- 4,5 0,495 0,506 0,517 O, 528 O, 540 0,551 0,562
- 4,o 0,495 0,507 0,518 O, 529 O, 540 0,551 0,562
0,496 0,507 0,519 O, 530 0,541 0,552 0,5?3
- 3,5
O, 530 0,553 0,564
- 3,o 0,491 0,508 0,519 0,542
- 2,5 0,498 0,509 O, 520 O, 531 O, 542 0,553 0,564
0,498 0,510 O, 521 O, 532 0,543 0,554 0,565
- 2,o
O, 521 O, 533 O, 544 0,555 0,5E5
- 1,5 0,499 0,51C
0,500 0,511 O, 522 O, 533 0,544 0,555 0,52;
* l,o
O, 523 @, 534 O, 545 0,556 0,567
- 0,5 0,501 0,512
0,501 0,512 0,524 0,535 O, 545 0,555 0,567
O, 0

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-9- ISO/R 91-1970/Add.l-1975 (E)
TABLE A
Reduction of density to 20 OC 0,500 to 0,590
O to 25°C
Observed hydrometer readmy -
Obs. I
temp.
0,500 0,510 0,520 0,530 0,540 0,55r? 0,560 0.570 Q,%O 0.590
'C
I
Corresponding density (kg/l) 20 "c
0,501 0,512 0,524 0,535 O, 545
O, 556 O, 567
O, 502 O, 51 3 0,524 0,535 O, 545
O, 557 O, 568
O, 503 0,514 0,525 0,536
O, 547 O, 558 O, 568
O, 504 0,515 0,526 0,537 O, 547 O, 558 O, 569
O, 504
0,515 0,526 0,537 O, 548 O, 559 O, 570
O, 505 0,516 0,527 0,538 O, 549 O, 560 O, 570
O, 495 O, 506 0,517 0,528 0,539 O, 549
O, 560 O, 571
O, 496 O, 507 0,517 0,528 0,539
O, 550 O, 561 0,571
O, 496 O, 507 0,518 0,529 0,540 O, 55 1
O, 561 O, 572
O, 497 O, 508 O, 51 9 0,530 0,540 3,55 1
O, 562 0,573
O, 498 O, 509 O, 520 0,530 0,541
O, 552 O, 563 O, 573
O, 499 0,510 O, 520 0.531 0.542 O, 552 O, 563 O, 574
O, 499
0,510 O, 521 0;532 0;542 0,553 O, 564 O, 574
O, 500 0,51 1 O, 522 0,532 0,543 O, 554 O, 564 O, 575
O, 501 0,512 O, 522 0,533 0,544 O, 554 O, 575
O, 565
O, 502 0,512
O, 523 0,534 0,544 O, 555 O, 566 0,576
O, 502 0,513 O, 524 0,534 0,545 O, 556 O, 566
O, 577
O, 503 0,514 O, 525 0,535 0,546 O, 556 O, 567 0,577
O, 504 0,515 O, 525
0,536 0,546 O, 557 O, 567 0,578
O, 505 0,515 O, 526 0,536 0,547 0,557 O, 568 O, 578
O, 495 O, 505 0,516 0,527 0,537 0,548 0,'558 0,568 0,579
O, 496 O, 506 0,517 0,527 0,538 0,548 O, 559
O, 569 0,579
O, 496 O, 507
0,517 O, 528 0,538 0,549 O, 559 O, 570 O, 580
O, 497 O, 508 0,518 O, 529 0,539 0,550 O, 560 O, 570 O, 581
O, 498 0,508 0,519 O, 529 0,540 0,550 0,571 0,581
0,561
O, 499 O, 509 O, 520 O, 530 0,540 0,551 0,561 O, 571 0,582
O, 500 0,510 O, 520 0,531
0,541 0,551 O, 562 O, 572 0,582
O, 500 0,511
0,521 0,531 0,542 0,552 O, 562 O, 573 O, 583
14,O O, 501
0,511 0,522 O, 532 0,542 0,553 O, 563 O, 573 O, 583
14,5 O, 502
0,512 0,522 O, 533 5,543 0,553 0,564 0,574 O, 584
e'
15,O 3,503 0,513
O, 523 O, 533 0,544 0,554 O, 564 O, 574 O, 585
15,5
O, 503 0,514 O, 524 O, 534 0,544 0,555 O, 565 O, 575 O, 585
16, O
O, 504 0,514 0,525 O, 535 0,545 0,555 O, 565 O, 575 O, 586
16,5
O, 495 O, 505 0,515 0,525 O, 535 0,546 0,555 0,566 O, 576 O, 586
17,0 O, 495 O, 506 0,516 O, 526 O, 536 0,546 0,556 O, 566 O, 587
O, 577
17,5 O, 496 O, 506 0,516 O, 527 O, 537 0,547 0,557 O, 567 0,587
O, 577
18, O O, 497 O, 507 0,517 O, 527 O, 537 0,547 0,558 0,568 O, 578 O, 588
18,5 O, 498 O, 508 0,518 O, 538 0,548 0,558 O, 568 0,578
O, 528 O, 588
19, O O, 598 O, 509 O, 51 9 O, 529 O, 539 0,549 0,559 O, 569 O, 579 O, 589
19,5 O, 499 O, 509 0,519 O, 529 O, 539 0,549 0,559 O, 569 O, 579 O, 589
20, O O, 500 O, 51 O O, 520 O, 530 O, 540 0,550 0,560 O, 570 O, 580 O, 590
O, 541
20,5 0,501 0,511 O, 521 O, 531 0,551 0,561 0,571 O, 581 0,591
21,o O, 502 3,511 O, 521 O, 531 O, 541 0,551 0,561 O, 571 O, 581 0,591
21,5 O, 502 0,512 O, 522 O, 532 O, 542 0,552 0,562 0,572 O, 582 O, 592
O, 572 O, 582 0,592
22, O O, 503 0,513 0,523 O, 533 O, 543 0,552 0,562
22.5 O, 504 0,514 0,523 O, 533 O, 543 0,553 0,563 O, 573 O, 583 0,593
23; O O, 505 O, 524 O, 534 O, 544 0,554 0,564 0,573 O, 583 O, 593
0,514
O, 545 0,554 0,564 0,574 O, 584 O, 594
23,5 O, 505 0,515 0,525 O, 535
O, 545 0,555 0,565 O, 575 O, 584 O, 594
24, O O, 506 0,516 0,526 O, 5 35
24,5 O, 507 0,516 O, 53ô O, 546 0,556 0,565 O, 575 O, 585 O, 593
0,526
O, 537 O, 546 0,556 0,566 0,576 O, 585 O, 595
25, O O, 507 0,517 0,527

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-10 -
ISO/R 91-1970/Add.l. 975 (
TABLE A
0,500 to 0,590
Reduction of density to 20 ' C
25 to 50" C
Observed hydrometer reading
Obs.
temp. 0.500 0,510 0,520 0,530 0,540 0,550 0,560 0,570 0,580 0,590
"C
Corrasoondino density (kg/ll 20 "C
25, O O, 507 0,517 O, 527
0,537 0,546 0,556 0,566
O, 576 O, 585 O, 595
25,5 O, 508 0,518 0,528
0,537 0,547 0,557 0,567
O, 576 O, 586 O, 596
26, O O, 509 O, 51 9
O, 528 0,538 0,548 0.557 0.567
O, 577 O, 587 O, 596
26,5 0,510
O, 51 9 O, 529 0,539 0,548
0;558 Ois68 O, 577 O, 587 O, 597
23, O 0,510 O, 520
O, 530 0,539 0,549 0,559 0,568
O, 578 O, 588 O, 597
' 27,5 0,511 O, 521 O, 530 0,540 0,550
0,559 0,569 0,579 O, 588
O, 598
28, O 0,512 0,521 O, 531 0,550
0,541 0,560 0,569 O, 579
O, 589 O, 598
28,5 0,513 O, 522 O, 532 0.541 0.551
0,560 0,570 O, 580
O, 589 0,599
29, O 0,513 O, 523 O, 532
0;542 0;551 0,561 0,571 O, 580 O, 590
O, 599
29,5 0,514 O, 524 O, 533
0,542 0,552 0,562 0,571
0,581 O, 590 O, 600
30, O 0,515 O, 524 O, 534 0,543 0,553
0,562 0,572 0,581 O, 591
O, 600
30,5 0,515 0,525 O, 534
0,544 0,553 0,563 0,572 O, 582 0,591
O, 601
31,O 0,516 0,526
O, 535 0,544 0,554 0,563 0,573
O, 582 O, 592 O, 601
31,5
0,517 O, 526 O, 536 0,545 0,554
0,564 0,573 0,583 O, 592 O, 602
32, O 0,518 3,527 O, 536 0,546 3,555
0,565 0,574 0,583 O, 593
O, 602
32,5 0,518 O, 528 O, 537
0,546 0,556 0,565 0,575 O, 584 O, 593
O, 603
33, O 0,519
O, 528 0,538 0,547 0,556 0,566 0,575
O, 584 O, 594 O, 603
33,5 0,520 O, 529 0,538
0,547 0,557 0,566 0.576 O, 585 O, 594 O, 604
34, O
O, 520 O, 530 O, 539 0,548 0,557 0;567 0;576 O, 585
O, 59s O, 604
34,5 0,521 O, 530 0,539 0,549 0,558
0,567 0,577 0, 586 O, 595 O, 605
35, O 0,531
0,522 O, 540 0,549 0,559 0,568 0,577 O, 586 O, 596 O, 605
35,5 0,522 O, 532 O, 541 0,550 0,559 0,569 0,578 0,587 0,596
O, 606
36, O 0,523 O, 532 O, 541 0,551 0,560
0,569 0,578 0,587 O, 596 O, 606
36,5 O, 524 O, 533 0,542
0,551 0,560 0,570 0,579 0,588 0,597 O, 607
37, O O, 524 O, 534
O, 543 0,552 0,561 0,570 0,580 0,588 O, 597 O, 607
37,5 0,525
O, 534 O, 543 0,552 0,562 0,571 0,580 O, 589 O, 598 O, 608
38, O O, 526 O, 535 O, 544
0,553 0,562 0,571 0,581 O, 589 O, 598 O, 608
38,5 0,526 O, 535
O, 544 0,554 0,563 0,572 0,581 O, 590 O, 599 O, 609
39, O
O, 527 O, 536 O, 545 0,554 0,563 0,573 0,582 O, 590 O, 599 O, 609
39,5 0,528 O, 537 O, 546 0,555 0,564 0,591
0,573 0,582 O, 600 O, 61 O
40, O O, 528 O, 537 O, 546 0,555 0,565 0,591
0,574 0,583 O, 601 O, 61 O
40,5 O, 529 O, 538 O, 547 0,556 0,565 O, 592
0,574 0,583 O, 601 0,611
41,O
O, 530 O, 539 O, 548 0,557 0,566 0,575 0.584 O, 592 O, 602 O, 61 1
41,5
O, 530 O, 539 0,548 0,557 0,566 0;575 0;584 O, 593 O, 602
O, 61 2
42, O O, 531 O, 540 O, 549 0,558 0,567 0,576 0,585 O, 593 O, 603
O, 61 2
42,5 O, 532 O, 540 O, 549 0,558 0,567 O, 594
0,576 0,585 O, 603 O, 61 3
43, O O, 532
O, 541 O, 550 0,559 0,568 0,577 0,586 O, 594 O, 604 O, 61 3
445 O, 533 O, 542 O, 55 1 0,560 0,569 0,578 0,586 O, 595 O, 604 0,613
44, O O, 534 O, 542 O, 55 1 0,560 0,569 O, 595 O, 604 0,614
0,578 0,587
44,5 0,534 O, 543 0,552 0,579 0,587 O, 595
0,561 0,570 O, 605 O, 61 4
45, O O, 535 O, 544 O, 552 0,561 0,570 0,579 0,587 O, 596 O, 605 0,615
-.
45,5 O, 553 0,562 0,571 0,580 0,588 O, 596 0,615
O, 536 O, 544 O, 606
46, O O, 536 O, 545 O, 554 0,562 0,571 0,580 0,588 O, 597
O, 606 O, 61 6
0,581 0,589 O, 597 O, 607 0,616
46,5 O, 537 O, 545 O, 554 0,563 0,572
47, O O, 537 O, 546 O, 555 0,564 0,572 0,581 0,589 0,598 O, 607 0,617
0,582 0,590 O, 598 0,617
47,5 O, 538 O, 547 O, 555 0,564 0,573 O, 608
0,582 0,590 O, 599 O, 608 0,618
48, O O, 539 O, 547 O, 556 0,565 0,574
48,5 O, 539 O, 548 O, 556 0,565 0,574 0,582 0,591 O, 599 O, 609 0,618
0,583 0,591 O, 599 O, 609 0,619
49, O O, 540 O, 548 O, 557 0,566 0,575
0,583 0,592 O, 600 O, 61 O 0,619
49,5 O, 540 O, 549 0,558 0,566 0,575
50, O 0,541 O, 550 0,558 0,567 0,576 0,584 0,592 O, 601 O, 61 O O, 620

---------------------- Page: 9 ----------------------
- 11 -
ISO!R 91-1970/Add.l-1975 (
TABLE A
0,600 to 0,690
Reduction of density to 20 C
-25 to O'C
Observed hydrometer reading
Obs.
temp. 0.600 0,610 0.620 0,630 0,640 0,650 0,660 0,670 0,580 0,690
\,C
Corresuondina densitv (kd) 20 "C
- 25,O 0,548 O, 560
0,572 O, 583 0,594 O, 605
0,616 O, 627 0,638 0,649
- 24,5 0,548
O, 561 0,572 0,583 O, 595
O, 606 O, 61 7 O, 628 0,639 0,649
- 24,O O, 549 0,561 0,573 O, 595
0,584 O, 606 0,617 O, 628 0,639 0,650
- 23,5 O, 550 O, 552 O, 573
O, 585 O, 596 O, 607 O, 61 8 O, 629 0,640 0,6504
- 23,O O, 550 O, 562 O, 574
O, 585 O, 597 O, 607 O, 61 8 O, 629 0,640 0,6509
- 22;5 O, 55 1
O, 563 O, 574 O, 586 0,597
O, 608 0,619 O, 630 0,641 0,6513
- 22,o
O, 552 O, 564 O, 575 O, 586 0,598 O, 609
O, 620 O, 630 0,641 0,6518
- 21,5 O, 552 O, 564
O, 576 0,587 O, 598 O, 609
O, 620 O, 631 0,642 0,6523
- 21,o O, 553
O, 565 O, 576 O, 587 O, 599
0,610 O, 621 O, 631
0,642 0,6528
- 20,5 O, 553 O, 565 O, 577
O, 588 O, 599 0,610 O, 621 O, 632 0,643 0,6532
- 20,o O, 554 O, 566 O, 577
O, 589 O, 600 0,611 O, 622 O, 632 0,643 0,6537
- 19,5 O, 555 O, 566 0,578 O, 589
O, 600 0,611 O, 622 O, 633 0,644 0,6542
- 19,0 O, 555 O, 567 O, 578
O, 590 O, 601 0,612 O, 623 O, 633 0,644 0,6547
- 18,5 O, 556
O, 568 O, 579 O, 590 O, 601 O, 61 2 O, 634
O, 623 0,645 0,6552
- 18,O O, 557
0,568 O, 579 0,591 O, 602 0,613
O, 624 O, 634 0,645 0,6556
- 17,5
O, 557 O, 569 O, 580 O, 591
O, 602 0,613 O, 624 O, 635 O, 646 0,6561
- 17,0 O, 558 O, 569 0,581
O, 592 O, 603 O, 61 4 O, 625 O, 635 0,646 0,6566
- 16,5 O, 558 O, 570
0,581 0,593 O, 603 O, 61 4 O, 625 O, 636
0,646 0,6570
- 16,O O, 559
0,571 O, 582 O, 593 O, 604 O, 626 O, 636 0,647 0,6575
0,615
- 15,5 O, 5 60 0,571
0,582 0,594 O, 605 0,615
O, 626 O, 637 0,647 0,6580
- 15,O O, 560 O, 572 0,583
O, 594 O, 605 0,616 O, 627 O, 637 0,648 0,6584
- 14,5 0,561
0,572 0,583 O, 595 O, 606 O, 61 6
O, 627 O, 638 0,648 0,6589
- 14,Q 0,562
O, 573 0,584 O, 595 O, 606 O, 61 7
O, 628 O, 638 0,649 0,6594
- 13,5 O, 562
O, 573 0,585 O, 596 O, 607
O, 61 7 O, 628 O, 639 0,649 0,6598
- 13,0
O, 563 0,574 O, 585
O, 597 O, 607 O, 61 8 O, 629 O, 639 0,650 0,6603
- 12,5 O, 5 63
O, 575 0,586 0,597 O, 608 0,619
O, 629 O, 640 O. 6503 O, 6608
- 12,0 O, 564
0,575 0,586 0,598
O, 608 0,619 O, 630 O, 640 O, 6508 O, 661 2
- 11,5
O, 565 O, 576 0,587 O, 598
O, 609 O, 620 O, 630 O, 641 0,6512 0,6617
- ll,o O, 5 65 O, 576 O, 587
O, 599 O, 609 O, 620 O, 631
O, 641 0,6517 0,6622
- 10,5 0,566
0,577 0,588 O, 599 0,610
O, 621 O, 631 O, 642 O, 6522 O, 5828
d'
- 10,o
O, 566 O, 577 O, 589
O, 600 0,610 O, 621 O, 632 O, 642 O, 6527 0,6631
- 9,5 O, 567 O, 578
0,589 O, 600 O, 61 1 O, 622 O, 632 O, 643 O, 6531 O, 6636
- 9,0 O, 568 O, 579
O, 590 O, 601 O, 61 1 O, 622 O, 633
O, 643 O, 6536 O, 6640
- 8,5
0,568 O, 579 O, 590 O, 601
O, 61 2 O, 623 O, 633 O, ç44 O, 6541 O, 6645
- 8,O O, 569 O, 580 0,591 O, 602
0,612 O, 623 O, 634 0,644 O, 6546 O, 6649
- 7,5 O, 569 O, 580
O, 592 O, 602 0,613 O, 624 O, 634 O, 645
O, 6550 O, 6654
- 7,o
0,570 0,581 O, 592 O, 603 0,614 O, 624 O, 635 O, 645
O. 6555 O. 6659
- 6,5 O, 570 O, 581 O, 593 O, 603 0,614
O, 625 O, 635 O, 646 O; 6560 O; 6663
- 6,O 0,571 O, 582 O, 593 O, 604 0,515
O, 625 O, 636 O, €46 O, 6564 O, 6669
- 5,5
O, 572 O, 583 O, 594 O, 604 O, 615 O, 636
O, 626 O, 646 O, 6569 O, 6672
- 5,o O, 572 O, 583 O, 594
O, 605 O, 61 6 O, 626 O, 637 O, 647 O, 6574 O, 6677
- 4,5
0,573 O, 584 O, 595 O, 605 0,616 O, €27 O, 637 O, 647
O, 6578 O, 5682
- 4,o
O, 573 O, 584 O, 595 O, 606 O, 61 7 O, 627 O, 638 0,648 O, 6583 O, 5686
- 3,5 O, 574 O, 585 0,59G O, 607 O, 61 7 O, 628 O, 638 O, 648
O, 6587 O, 6691
- 3,o O, 575 O, 586 O, 597
O, 607 0,618 O, 628 O, 639 O, 649 O, 6592 O, 6695
- 2,5
O, 575 O, 586 O, 597 O, 608 O, 61 8 O, 529 O, 639 O, 649 0,5597 0,6700
- 2,o 0,576 0,587 0,598 O, 608 O, 61 9 O, 629 O, 650 O, 6601 O, 6704
O, 639
- 1,5 0,576 O, 587 O, 598 O, 609 O, 61 9 O, 640 O, 6503
0,6605 0,6709
0,630
- l,o O, 577 O, 588 0,599 O, 609
O, 620 O, 630 O, 640 O, 6508 C, 661 1 C, CÏ1 3
- 0,5 O, 571 0,588 0,599 0,610 O, 620 O, 631 0,641 O, 651 2 O, 661 5 O, 671 8
0,578 0,589 O, 600 O, 61 O O, 621 O, 631 O, 641 O, 65? 7 O, 6620 O, 6723
O, 0

---------------------- Page: 10 ----------------------
- 12 -
ISO/R 91-1970/Add.l-1975 (E)
TABLE A
0,600 to 0,690
Reduction of density to 20 "C
O to 25°C
Observed hydrometer reading
Obr. 1
Wmp. 0,600 0,610 0,620 0,630 0,640 0,650 0.660 0,670 0.tjsO 0,690
"C I
Corresaondina density (kg/ll 20 "C
O, 578
O, 589 0,600 0,610 O, 621
O, 0 O, 631 O, 641 0,6517 0,6620 0,6723
O. 5 O, 579 O, 590
0,600 0,611 O, 621 O, 632 O, 642 O, 6522 O, 6624 O, 6727
1; O 0,579
0,590 0,601 0,611 O, 622 O, 632
O, 642 O, 6526 O, 6629 O, 6732
0,580 0,591 0,601 0,612 O, 622
1,5 O, 632 O, 643 O, 6531 O, 6634 O, 6736
O, 580 O, 591 0,602 0,612 O, 623 O, 633
290 O, 643 O, 6536 O, 6638 O, 6741
0,581
O, 592 0,602 0,613 O, 623 O, 633 O, 644
2,5 O, 6540 O, 6643 O, 6745
0,581 O, 592 0,603 0,613 O, 624 O, 634
390 O, 644 O, 6545 O, 6647 O, 6750
0,582 O, 593 0,603 0,614
395 O, 624 O, 634 O, 645 O, 6550 O, 6652 O, 6754
0,583 O, 593 0,634 0,614
490 O, 625 O, 655 O, 645 O, 6554 O, 6656 O, 6753
0,583 O, 594
0,604 0,615 O, 625 O, 635 O, 646 O, 6559 O, 6661 O, 6763'
495
O, 584 O, 595 0,605 0,615 O, 626 O, 636 O, 646
590 O, 6564 O, 6666 O, 6768
0,584 O, 595 0,605 0,616 O, 626 O, 636
595 O, 647 O, 6568 O, 6670 O, 6772
0,585 O, 596 0,606 0,616 O, 627 O, 637
570 O, 647 O, 6573 O, 6675 O, 6777
6,5 c, 585 O, 596
0,606 0,617 O, 627 O, 637 O, 648 O, 6577 O, 6679 O, 6781
0,586 O, 597 0,607 0,617 O, 628 O, 638 O, 648 O, 6582 O, 6684
7,0 O, 6786
O, 587 O, 597 0,607 0,618 O, 628 O, 638
795 O, 648 O, 6587 O, 6688 O, 6790
O, 587 O, 598 0,608 0,618 O, 639
890 O, 629 O, 649 O, 6591 O, 6693 O, 6794
I
0,588
O, 598 0,609 0,619 O, 629 O, 639 O, 649 O, 6596 O, 6697 O, 6799
8, 5
O, 588 O, 599 0,609 0,619 O, 629 O, 640 O, 650
990 O, 6600 O, 6702 O, 6803
O, 589 O, 599 0,610 0,620 O, 640 O, 6503
9,5 O, 630 0,6605 0,6706 0,6808
10,o 0,589 O, 600 0,610 0,620
O, 630 O, 641 O, 6508 0,6610 0,6711 0,6812
1 O, 5 0,590
O, 600 0,611 0,621 O, 631 O, 641 0,6513 0,6614 0,6715 0,6817
ll,o
0,591 O, 601 0,611 0,621 O, 631 O, 642 0,6517 O, 661 9 O, 6720 O, 6821
11,5 0,591 O, 601 0,612 0,622 O, 632 O, 6522
O, 642 O, 6623 O, 6724 O, 6825
12,o O, 592 O, 602 0,612 0,622
O, 632 O, 643 O, 6527 O, 6628 O, 6729 O, 6830
12,5
0,592 O, 602 0,613 0,623 O, 633 O, 643 O, 6531 O, 6632 O, 6733 O, 6834
13,O 0,593 O, 603 0,613. 0,623
O, 633 O, 643 O, 6536 O, 6637 O, 6738 O, 6839
13,5 0,593 O, 603
0,614 0,624 O, 634 O, 644 O, 6540 O, 6641 O, 6742 O, 6843
14,O
O, 594 O, 604 0,614 0,624 O, 634 O, 644 O, 6545 O, 6646 O, 6747 O, 6848
, *'
14,5 0,594 O, 604 0,615 0,625 O, 635 O, 645 O, 6550 O, 6650 O, 675 1 O, 6852
15,O O, 595 O, 605 0,615 0,625 O, 635 O, 645 O, 6554 O? 6655 O, 6756 O, 6856
15,5 O, 595 O, 605 0,616 0,62û O, 636 O, 646 O, 6559 O, 6660 O, 6760 O, 6861
16,O O, 596 O, 606 0,616 0,626 O, 636 O, 65 63 O, 6765 O, 6865
O, 646 O, 6664
16,5 O, 596 O, 606 0,617 0,627
O, 637 O, 647 O, 6568 O, 6669 O, 6769 O, 6869
17,O O, 597 O, 607 0,617 0,627 O, 637 O, 647 O, 6573 0,6673 0,6773 0,6874
17,5 0,597 O, 607 0,618 0,628 O, 638 O, 648 O, 6577 O, 6678 O, 6778 O, 6878
18,O O, 598 O, 608 0,618 0,628 O, 6582 O, 6782 O, 6883
O, 638 O, 648 O, 6682
18,5 O, 598 O, 608 0,619 0,629 O, 639 O, 649 O, 6586 O, 6687 O, 6787 0,6887
19,0 O, 599 O, 609 0,619 0,629 O, 639 O, 649 O, 6591 O, 6691 O, 6791 O, 6891
19,s O, 599 0,610 0,620 0,630 O, 640 O, 650 O, 6595 O, 6696 O, 6796 O, 6896
O. 6700 O. 6800 O, 6900
20, O O, 600 0,610 0,620 0,630 O, 640 O. 650 O, 6600
20,5 O, 601 0,610 0,620 0,630 O, 640 O; 6505 O, 6605 O; 6704 O; 6804 O; 6904
O, 641 O, 6509 O, 6609 O, 6709 O, 6809 O, 6909
21,o O, 601 O, 61 1 0,621 0,631
0,6713 0,6813 O, 691 3
21,5 O, 602 O, 61 1 0,621 0,631 O, 641 0,6514 O, 661 4
0,6917
22, O O, 602 O, 61 2 0,622 0,632 O, 642 0,6518 0,6618 O, 671 8 O, 681 8
O, 642 O, 6523 O, 6623 O, 6722 O, 6822 O, 6922
22,s O, 603 O, 61 2 0.622 0.632
O, 643 O, 6528 O, 6627 O, 6727 O, 6826 O, 6926
23, O O, 603 0,613 0;623 0;633
O, 643 O, 6532 O, 6731 O, 6831 O, 6930
23,5 O, 604 0,613 0,623 0,633 O, 6632
O, 6537 O, 6636 O, 6736 O, 6835 O, 6935
24, O O, 604 0,614 0,624 0,634 O, 644
O, 644 O, 6541 O, 6641 O, 6740 O, 6839 O, 6939
24,5 O, 605 0,614 0,624 0,634
O, 6943
O, 645 O, 6546 O, 6645 O, 6745 O, 6844
25, O O, 605 0,615 0,625 0,635

---------------------- Page: 11 ----------------------
- 13- ISOIR 91-1970/Add.l-1975 (
TABLE A
Reduction of density to 20 "C 0,600 to 0,690
25 to 5o'c
Observed hydrometer reading
II I
Obs.
temp.
0,600 0.610 0,620 0,630 0,640 0.650 0,660 0,670 0,680 0,690
"C
I
Corresponding density (kg/ll 20 "C
25, O O, 605 0,615 0,625 0,635 0,645
O, 6546 O, 6645 O, 6745 O, 6844 O, 6943
25,5 O, 606 0,615 0,625
0,635 0,645 O, 6550 O, 6650 O, 6749 O, 6848 O, 6947
26, O O, 606 0,616
0,626 0,636 0,646 O, 6555 O, 6654 O, 6753 O, 6853 O, 6952
26,5 O, 607
0,616 0,626 0,636 0,646 O, 6560 O, 6659 O, 6758 O, 6857 O, 6956
27, O O, 607 0,617 0,627 0,637 O, 6564 O, 6762
0,647 O, 6663 O, 6861 O, 6960
27,5 O, 608
0,617 0,627 0,637 0,647 O, 6569 O, 6668 O, 67 67 O, 6866 O, 6965
28, O O, 608
0,618 0,628 0,638 0,647 O, 6573 O, 6672 O, 6771 O, 6870 O, 6969
28,5
O, 609 0,618 0,628 0,638 0,648 O, 6578 O, 6677 O, 6775 O, 6874 O, 6973
29, O O, 609 U,619 0,629
0,636 0,648 O, 65&2 O, 6681 O, 6760 O, 6873 O, 6977
29,5 O, 61 O 0,619
0,629 0,639 0,649 O, 6587 O, 6685 O, 6784 O, 6883 O, 6982
30,.0
0,610 0,620 0,630 0,639 0,649 O, 6591 O, 6690 O, 6789 O, 6887 O, 6986
30,5
0,611 0,620 0,630 0,640 0,650 O, 6596 O, 6694 O, 6793 O, 6892 O, 6990
31,O 0,611 0,621 0,631 O, 6797 O, 6896 O, 6994
0,640 0,6502 O, 6600 O, 6699
31,5 0,611 0,621 0,631 0,641 O, 6605 O,
...