United States       Prevention, Pesticides      EPA712-C-96-032
          Environmental Protection    and Toxic Substances      August 1996
          Agency         (7101)
&EPA    Product Properties
           Test Guidelines
           OPPTS 830.7100

     This guideline is one  of a series  of test guidelines  that have been
developed by the Office of Prevention, Pesticides and Toxic Substances,
United States Environmental Protection Agency for use in the testing  of
pesticides and toxic substances, and the  development of test data that must
be submitted to the Agency  for review under Federal regulations.

     The Office of Prevention, Pesticides and Toxic Substances (OPPTS)
has  developed this guideline through  a  process of harmonization that
blended the testing  guidance and requirements that existed in the Office
of Pollution Prevention and Toxics  (OPPT) and appeared in Title 40,
Chapter I,  Subchapter R of the Code of Federal Regulations  (CFR), the
Office of Pesticide Programs (OPP) which appeared in publications of the
National Technical  Information Service (NTIS) and  the guidelines pub-
lished by the Organization  for Economic Cooperation and Development

     The purpose of harmonizing these guidelines into a single set  of
OPPTS  guidelines is to minimize variations among the testing procedures
that must be performed to meet the data  requirements of the U. S. Environ-
mental Protection Agency  under the Toxic  Substances Control Act (15
U.S.C. 2601) and the Federal Insecticide,  Fungicide and Rodenticide Act
(7U.S.C. I36,etseq.).

     Final  Guideline Release: This document is available from the U.S.
Government Printing Office, Washington, DC 20402 on The Federal Bul-
letin  Board.   By  modem  dial   202-512-1387,   telnet   and  ftp:
fedbbs.access.gpo.gov     (IP,    internet:     http://
fedbbs.access.gpo.gov, or call 202-512-0132 for disks or paper copies.
This guideline is available in ASCII and PDF (portable document format)
from the EPA Public Access Gopher (gopher.epa.gov) under the heading
"Environmental Test Methods and Guidelines."

      OPPTS 830.7100  Viscosity.
           (a) Scope—(1) Applicability. This guideline is intended to meet test-
      ing  requirements  of both  the  Federal  Insecticide,  Fungicide,  and
      Rodenticide Act (FIFRA) (7 U.S.C. 136, et seq.) and the Toxic Substances
      Control Act (TSCA) (15 U.S.C. 2601).

           (2) Background. The source materials used in developing this har-
      monized OPPTS test  guideline are OPP  guideline 63-18 Viscosity (Pes-
      ticide Assessment Guidelines, Subdivision D: Product Chemistry, EPA Re-
      port 540/9-82-018, October 1982) and OECD guideline 114 Viscosity of

           (b) Introductory information—(1)  Prerequisite. Density, for the
      rolling ball viscometer method.

           (2) Guidance information, (i) Melting point/melting range.

           (ii) Boiling point/boiling range.

           (3) Coefficient of variation. Coefficients of variation appeared to  be
      dependent  on the  chemicals tested. They are calculated from the  mean
      values given by the participants of the OECD Laboratory Intercomparison
      Testing, part I, 1979,  and their range is from 0.004 to 0.09, without refer-
      ring to different methods applicable.

           (4) Qualifying statement. The five methods  listed are  appropriate
      in principle for the investigation of Newtonian liquids. The measurement
      of non-Newtonian liquids  is only possible with the rotational viscometer.

           (5) Additional comments. These methods are capable  of greater pre-
      cision than is  likely  to be required for environmental assessment. The
      ranges are shown in the following table 1:
                         Table  1.—Measurement of Precision
Capillary viscometer 	
Flow cup 	
Rotational viscometer ....
Rolling ball viscometer ..
Drawing ball viscometer
0.5 mPa s to 105 mPa s
8 mPa s to 700 mPa s
10 mPa s to 109 mPa s
0.5 mPa s to 105 mPa s
0.5 mpa s to 107 mpa s
           (6) Standard documents, (i) The majority of the methods described
      is based on both international and national standards. The appropriate ISO
      Standards describing the concerned methods are  cited within the text of
      this test guideline (see paragraph (f)(3) of this guideline).

           (ii) A good summary of measuring instruments and measuring meth-
      ods can be found under paragraph (f)(2) of this guideline.

     (c) Method—(1) Introduction, purpose, scope, relevance, applica-
tion and limits of test, (i) The viscosity of fluids is environmentally rel-
evant owing to the penetration of fluids into the soil and the harmful effect
on the ground water  which may thus possibly be caused. From the point
of view of this problem, surface tension as well as questions of wettability,
miscibility or solubility play, a part in addition to  viscosity, so that it is
usually not sufficient  to consider viscosity alone.

     (ii) There is no environmentally relevant limit in the direction of low
viscosities. The lower the viscosity the more easily a fluid seeps into the
soil. The lowest dynamic viscosity of liquids occurring at room tempera-
ture is approximately 0.2 mPa  s,  that is  to  say  one-fifth of the viscosity
of water at 20 °C. A limit in  the direction  of high viscosities cannot be
precisely quoted. Dynamic viscosities above approximately 107 mPa s are
so high that penetration into the soil is no longer probable.

     (iii) In the case of substances which have a yield value (pastes, oint-
ments), the substance may still not penetrate into  the soil, although the
dynamic viscosity may be low after the yield value  has been exceeded.
If the  substance is soluble in water or can  be emulsified, environmental
damage may occur despite the existence of a  flow limit.

     (2) Definitions  and  units. Viscosity is the property of a fluid sub-
stance of absorbing a stress during deformation which depends on the rate
of the deformation. Similarly, the stress  can be regarded as the cause which
brings about a deformation rate.

     (i) The shear stress, T, and the shear rate, D, are  related by the equa-

                       T = T|D

T| is defined as the dynamic viscosity.

     (ii) For Newtonian liquids, the viscosity is constant at all shear rates
and depends only on the variables pressure and temperature.

     (iii) For  non-Newtonian liquids,  the viscosity will vary with shear

     (iv) If the viscosity is measured with capillary viscometers without
applied pressure, the  measured quantity obtained is the ratio of dynamic
viscosity to density, the so-called kinematic viscosity, v.

     (v) The  SI unit of dynamic viscosity is the Pascal second, Pa s. For
practical use a submultiple is more convenient; 1 mPa s  = 10-3 Pa s (one
centipoise [cP] in the  obsolete cgs-system).

     (vi) The SI unit of kinematic viscosity is the square meter per second,
m2/s. The normal sub unit derived from this is the square millimeter per

        second, mm2/s =  10'6 m2/s.  (1  mm2/s =  1  centistoke [cSt] in the obsolete

             (3) Reference substances, (i) The reference substances need not be
        employed in all cases when investigating a new substance. They are pro-
        vided  primarily so that calibration of the method may be performed from
        time to time and to offer the chance to  compare the results when another
        method is applied.

             (ii) The following list of reference substances has been extracted from
        that recommended by the IUPAC.
                  Table 2.—Recommended Reference Substances for Viscosity Measurements
       Chemical Name
                              Certified Value and Accuracy
Series of  mineral  oils  (hydro-
  carbons,  partly natural, partly
  synthetic products).
Type OS 2.5-2,000 (series of 10
Type60H  ...

Type 200 H

Mineral oil ...
Mineral oil 	


Series of 11 mineral oils
Series of 7 polyisobutylenes
1 to 27,000 mPa s (1.25 to 30,000
  mm2/sec at 20 °C. Uncertainty,
  ±0.2%, above  4,000  mPa  s
Certified for viscosity in  mPa s
  and  kinematice  viscosity  in
  mm2/sec .  Range  for viscosity
  at 20 °C from 2 to 8,000

60,000 mrrWsec at 20 °C

200,000 mrrWsec at 20 rC

11 to 1,000 mPa s ±0.1% at 20

103 to 104 mPa s ±0.5% at 20 °C

104 to 105 mPa s ±1.5% at 20 °C

Certified for viscosity in mPa s at
  20 °C. Rnage from 1.503 ±0.1%
  to 1,729 ±0.2%

Certified for viscosity in mPa s at
  20 C. Range from 4,170 ±1.3%
  to 589 x ±1.0%
          Newtonian liquids, determined by
           capillary viscometers with  sus-
           pended level (Ubbelohde). Data
           also for other temperatures be-
           tween 20 and 100 °C.



          Newtonian liquid. Certified also for
           density and kinematic viscosity

          Newtonian liquid. Certified also for
           density and kinematic viscosity.

          Newtonian liquid. Rotating cylinder
           viscometer method used.

          Certified also for kinematic viscos-
           ity and density. Data also at 50
           °C and 80 °C.

          Data also at 50, 80, and 100 °C.
  1 Units are given as reported by issuing laboratory. The letter references in column three indicating the countries reporting rep-
resent the following countries:
  C: Germany: The Physikalische-Technische Bundesanstalt, 33 Braunschweig, Bundesallee 100, Federal Republic of Germany.
  D: Hungary: National Office of Measures Nemerolgyi ut 37-39 sz. Budapest XII, Hungary.
  E: Japan: National Chemical  Laboratory for Industry,  Ministry of International Trade &  Industry, 1-1 Honmachi, Shibuya-ku,
Tokyo 151, Japan.
  G: Poland: Division of Physico-Chemical Metrology,  National Board for Quality Control and Measures - 2, Elektoalna St., War-
saw, Poland.

             (4) Principle of the test method. Viscosity measurements are carried

       out predominantly according to three measurement principles:

             (i)  The flow under gravity through a capillary, (capillary viscometer

       or flow cup).

             (ii) Shearing of the fluid  between  concentric cylinders,  coneplate  and

       parallel plate (rotational viscometer).

             (iii) (A) Dynamic viscosity can be measured by movement of a  ball

       in a vertical or inclined liquid-filled cylindrical tube  (e.g.  a rolling  ball

       viscometer by Hoppler, drawing ball viscometer, etc.)

    (B) With the Hoppler viscometer the density must be known in order
to calculate the dynamic viscosity.
    (5) Quality criteria. The various methods of determining viscosity
of  liquids  are  compared  as  to  application,   measuring  range  and
standardizability in the following table.
                     Table 3.—Comparison of the Methods
Method of Measurement
Capillary viscometer 	
Flow cup 	
Rotational viscometer 	
Rolling ball viscometer 	
Drawing ball viscometer

(mPa s)
(mPa s or
0.5-1 07
ISO 3104 and 3105 ...
ISO 3104 amd 3105 ..
ISO 3218.2 	
no international stand-
ards, see DIN
no international stand-
ards, see DIN
52007, part 2 (draft).
ture Con-
stancy re-
quired (°C)
    (i)  Possibility of standardization. See table 3 in paragraph (c)(5) of
this guideline.

    (ii) Possibility of automation. Yes.

    (d) Description of the test method—(1) Preparations-apparatus.
(i) Capillary viscometer designs are  described in: ISO 3104; ISO 3105;
DIN 51550; DIN 51550; DIN 51562 part 1; DIN 51561; DIN 51366, DIN
51372; DIN 53177; ASTM D-1200-70; ASTM  D-2393; ASTM D-914
part 25  to 37; ASTM D-88-56. Refer to  paragraph (f) of this  guideline
for more information.

    (ii) The standardization of rotational viscometers covers, with few ex-
ceptions, only general specifications concerning  the  flow pattern, range
of shearing stresses to be used and velocity gradient as well as specifica-
tion relating to specific  substances.  ISO  3219-1977; DIN 51398; DIN
51377; DIN 53214; DIN 53019 part 1; DIN 53229; DIN 52312 part 2;
DIN 53921; ASTM D-562-55; ASTM D-3346-74; ASTM D-2983. Refer
to paragraph (f) of this guideline for more information.

    (iii) Forced ball viscometers are only standardized in such national
standards as:  DIN 53015, DIN 52007 part 2 and ASTM D-914 part  25
to part 37.  Refer to paragraph (f) of this guideline for more information.

    (2) Test conditions. Each determination of viscosity must be accom-
panied by the temperature at which the measurement was made. The deter-
mination should preferably be made at a temperature of 20 °C and at one
other  temperature approximately 20 °C  higher (see table 1 in paragraph
(c)(3)(ii) of this guideline for temperature control limits). At least two de-
terminations should be made at each temperature.

     (3) Performance of the tests. The measurement is carried out accord-
ing to the specifications in the respective standards.

     (e) Data and reporting—(1) Treatment of the results, (i) The eval-
uation of the viscosity measurement is to be carried out according to the
standards in the case of capillary and  forced ball viscometers. In the case
of rotational viscometers, the specification of a viscosity is appropriate
only for Newtonian fluids.  For non-Newtonian fluids the results obtained
are preferred in the form of flow curves which must be interpreted, assum-
ing the validity of various laws of flow.

     (ii) The uncertainties in the measurement are quoted in the standards
for capillary, forced ball and rotational viscometers.

     (2) Test report (detailed conduct  of test and evaluation). The test
report is to be drafted in accordance with the specifications  in the stand-
ards. It must include individual and mean values at each temperature. Any
variation from the standard method must be described in detail.

     (f) References. The  following references should be  consulted for ad-
ditional background material on this test guideline.

     (1) Physicochemical Measurements: Catalogue of Reference Materials
from National Laboratories, in: Pure and Applied Chemistry,  IUPAC, vol.
48, pp. 513-514, Pergamon Press (1976).

     (2) Wazer, W. et al. Viscosity and Flow Measurement, Laboratory
Handbook ofRheology, Inst. Publ. New York - London (1963).

     (3) International Organization for Standards, ISO. American National
Standards Institute,  Sales Department,  1430 Broadway, New  York, NY
10018. Book of Standards (latest edition).

     (4) Das 1st Norm., DIN.  American National Standards Institute, Sales
Department, 1430 Broadway, New York, NY  10018.  Book  of Standards
(latest edition).

     (5) American Society for Testing and Materials,  ASTM,  1916 Race
St., Philadelphia PA 19103. Annual  Book of ASTM Standards  (latest edi-

     (6) Organization for Economic Cooperation and Development, Guide-
lines for The Testing of Chemicals, OECD  114 Viscosity of Liquids,
OECD, Paris, France.