is.3025.14.1984 - ISO 7888.pdf

इंटरनेट

मानक

Disclosure to Promote the Right To Information Whereas the Parliament of India has set out to provide a practical regime of right to information for citizens to secure access to information under the control of public authorities, in order to promote transparency and accountability in the working of every public authority, and whereas the attached publication of the Bureau of Indian Standards is of particular interest to the public, particularly disadvantaged communities and those engaged in the pursuit of education and knowledge, the attached public safety standard is made available to promote the timely dissemination of this information in an accurate manner to the public. “जान1 का अ+धकार, जी1 का अ+धकार”

“प0रा1 को छोड न' 5 तरफ”

“The Right to Information, The Right to Live”

“Step Out From the Old to the New”

Mazdoor Kisan Shakti Sangathan

Jawaharlal Nehru

IS 3025-14 (1984): Methods of sampling and test (physical and chemical) for water and wastewater, Part 14: Specific conductance (wheatstone bridge, conductance cell) [CHD 32: Environmental Protection and Waste Management]

“!ान $ एक न' भारत का +नम-ण” Satyanarayan Gangaram Pitroda

“Invent a New India Using Knowledge”

“!ान एक ऐसा खजाना > जो कभी च0राया नहB जा सकता ह” है” ह Bhartṛhari—Nītiśatakam

“Knowledge is such a treasure which cannot be stolen”

IS 3025 (Part 14) : 2013 ISO 7888 : 1985

Hkkjrh; ekud

ty vkSj vif'k"V ty osQ uewus ysus rFkk ijh{k.k (HkkSfrd ,oa jlk;u) i¼fr;k¡ Hkkx 14 fof'kf"V pkydrk (ohVLVksu] fczt] pkydrk lsy)

( nwljk iqujh{k.k ) Indian Standard METHODS OF SAMPLING AND TEST (PHYSICAL AND CHEMICAL) FOR WATER AND WASTE WATER PART 14 SPECIFIC CONDUCTANCE (WHEATSTONE BRIDGE, CONDUCTANCE CELL)

( Second Revision )

ICS NO. 13.060.60

© BIS 2013

BUREAU OF INDIAN STANDARDS MANAK BHAVAN, 9 BAHADUR SHAH ZAFAR MARG NEW DELHI 110002 January 2013

Price Group 3

Environment Protection and Waste Management (Excluding Biomedical and Nuclear Waste) Sectional Committee, CHD 32

NATIONAL FOREWORD This Indian Standard (Part 14) (Second Revision) which is identical with ISO 7888 : 1985 ‘Water quality — Determination of electrical conductivity’ issued by the International Organization for Standardization (ISO) was adopted by the Bureau of Indian Standards on the recommendation of the Environment Protection and Waste Management (Excluding Biomedical and Nuclear Waste) Sectional Committee and approval of the Chemical Division Council. The first revision of this standard was published in 1984 by superseding 9 of IS 3025 : 1964 ‘Methods of sampling and test (physical and chemical) for water used in Industry’. This second revision has been undertaken to harmonize it with the latest development that have taken place at international level. The committee has now decided to adopt this standard under dual numbering system. The text of ISO Standard has been approved as suitable for publication as an Indian Standard without deviations. Certain conventions are, however, not identical to those used in Indian Standards. Attention is particularly drawn to the following: a) Wherever the words ‘International Standard’ appear referring to this standard, they should be read as ‘Indian Standard’. b) Comma (,) has been used as a decimal marker while in Indian Standards, the current practice is to use a point (.) as the decimal marker. In reporting the result of a test or analysis made in accordance with this standard, if the final value, observed or calculated, is to be rounded off, it shall be done in accordance with IS 2 : 1960 ‘Rules for rounding off numerical values (revised)’.

~-

INTERNATIONAL

IS 3025 (Part 14) : 2013 ISO : 78884985 (E) ISO 7888 1985

STANDARD

Indian Standard METHODS OF SAMPLING AND TEST (PHYSICAL AND CHEMICAL) FOR WATER AND WASTE WATER 14 SPECIFIC CONDUCTANCE (WHEATSTONE BRIDGE, CONDUCTANCE CELL) of electrical conductivity WaterPARTquality - Determination

( Second Revision )

1

Scope

and field

of application

This International Standard specifies measurement of the electrical conductivity

where I

a method for the of all types of water.

is the length,

in metres,

of an electrical

A Electrical

conductivity

tan be used to monitor

a)

surface waters;

b)

process waters

c)

waste waters.

the quality

is the effective Cross-sectional an electrical conductor.

of

area, in Square metres, of

The cell constant results from the geometry empirically determined. in water supply

and treatment

conductor;

of the cell; it tan be

plants;

2.3

The completeness of analysis for ionic constituents[l be checked using this method.

10 31 tan

temperature coefficient of electrical conductivity,*) a: The temperature coefficient of conductivity ae r 25,M is given by the equation

51

x 100 In some cases absolute values are important, only relative changes are of concern. For interferences,

in other

cases where 25 and 0 OC are the temperatures at which the electrical conductivities ~25 and ye respectively were measured.

see clause 9.

2.4

2

Definitions

correct tivity.

2.1 specific conductance; electrical conductivity, y: The reciprocal of the resistance, measured under specified conditions, between the opposite faces of a unit cube of defined dimensions of an aqueous Solution. For water quality examinaconductivity” and tion, this is often expressed as “electrical may be used as a measure of the concentration of ionizable solutes present in the Sample. (Definition

f: Factors used to of electrical conduc-

In Order to make comparisons, it is essential that measurements are corrected to a Chosen reference temperature, usually 25,0 OC, even if the temperature of the water Sample differs only slightly from that temperature. Conversions to the electrical made using the equation

conductivity

at 25 OC, ~25, tan be

taken from ISO 6107/2.)

lt is expressed

y25 = 1 + (a/lOO) (8 - 25)

in Siemens per metre?

NOTE - The Symbols (sec ISO 31/5).

0 and K are also used for electrical

conductivity

where a

2.2

cell constant, by the equation

K=-

temperature correction factors, for the temperature dependence

K:

Quantity,

in reciprocal

metres,

given

is the temperature

Yo is the electrical ; perature,

e

1

0 is the measuring Sample.

A

1)

1 S/m

2)

The temperature

= IO4 pS/cm

coefficient

of electrical

conductivity

at the

temperature,

conductivity;

measured

tem-

in degrees Celsius, of the

= IO3 mS/m

coefficient

of electrical

conductivity

tan be expressed

in reciprocal

kelvin

or Yo per OC.

1

ISO 78884985

(El

IS 3025 (Part 14) : 2013 ISO 7888 : 1985

3

Principle

Table

Direct determination, using an appropriate instrument, of the electrical conductivity of aqueous solutions. The electrical conductivity is a measure of the current conducted by ions present in the water (“phenomenon of conductors of the second kind”), and depends on a) b)

the concentration

1 -

Electrical conductivity chloride solutions

Concentration chloride,

of potassium c( KCI)

of potassium

Electrical conductivity at 25 OC, yz5

mol/1

mS/m 7,4 14,7

0,000 5 0,001

of the ions;

the nature of the ions;

0,005

72

0,Ol

141

0,02

277 670

0,05

c) d)

the temperature the viscosity

Pure water conductivity

4

of the Solution;

During the analysis, unless otherwise of recognized analytical grade.

stated,

use only reagents

4.1 Water for preparing solutions and dilutions. distilled or de-ionized water; the electrical conductivity Y25