Type of reference material

Status

Certified Values

Range значений

Relative

uncertainty (relative error)

Method of characterization

1

2

3

4

3

INORGANIC REFERENCE MATERIALS (А2)

Aqueous solutions of cations monocomponent

(А2.6.1)

CRM

Mass concentration of ion

0,0475 – 10,5 g/dm³

0,25 – 1 %

Primary methods in one laboratory: constant-potential coulometry, coulometric titration, gravimetry.

Secondary methods based on certified measurement procedures, using CRM, certified by primary method: titration, AC conductometry

Aqueous solutions of anions monocomponent

 (А2.6.2)

CRM

Mass (molar) concentration of ion

0,095 – 10,5 g/dm³

(0,97 – 1,03 mol/dm³)

0,25 – 2 %

(0,5%)

Primary methods in one laboratory: coulometric titration, gravimetry.

Secondary methods based on certified measurement procedures, using CRM, certified by primary method: titration, AC conductometry, spectrophotometry

Aqueous solutions of

metals multicomponent (А2.6.3)

CRM

Mass concentration of metal

0,095 – 0,525 g/dm³

2 %

Secondary methods based on certified measurement procedures, using CRM, certified by primary method: spectrometry with inductively coupled plasma.

ORGANIC REFERENCE MATERIALS (А3)

Pure chemical substances

(А3.1.1)

CRM

Molar ratio of

organic basic component

99,30 – 99,98 %

0,04 – 0,14 %*

Primary methods in one laboratory: cryometry.

Solutions of organic substances in organic solvents (А3.1.2)

CRM

Mass concentration of organic substance

0,095 – 52,5 g/dm³

2,0 – 4,0 %

Secondary methods based on certified measurement procedures, using CRM, certified by primary method: gas chromatography

Standards for chromatography (А3.1.3)

RM

Mass ratio of

basic component

99,30 – 99,99 %

0,2 – 3 %**

Secondary methods: gas chromatography

REFERENCE MATERIALS for environmental analysis (А4)

Properties of aqueous media (А4.3.1)

CRM

Turbidity

3800 - 4200 FTU

(formazine turbidity units)

2,0 %

Secondary methods, based on use of precise measuring instruments and secondary measuring standards: spectrophotometry

Color

475 - 525 degrees of color

(in accordance with the ISC*** standard GOST 31868-2012

1,5 %

Total hardness

9,5 – 105 degrees of hardness

(in accordance with the ISC*** standard GOST 31865-2012)

1,5 %

Secondary methods  based on certified measurement procedures, using CRM, certified by primary method: titration

COD (dichromate oxidation of water)

9500 - 10500 mg/dm³

1,5 %

Total alkalinity

950 – 1050  mmol/dm³

1 %

TDS

47500 – 52500 mg/dm³

1 %

Primary methods in one laboratory:  gravimetry

Organic pollutants

(А4.3.2)

RM

Mass of oils in water soluble matrix

6,5 – 0,015 mg

2,5 – 4,0 %**

Primary methods in one laboratory:  gravimetry

ION ACTIVITY (А9)

Standards of рН (А9.1)

CRM

рН

1,65 - 9,18

0,01 рН*

Secondary methods, based on use of precise measuring instruments and secondary measuring standards: potentiometry

Standards of electrical conductivity

(А9.3)

CRM

Specific electrical conductivity

0,0045 – 11,8 Sm/m

0,25 %

Secondary methods, based on use of precise measuring instruments and secondary measuring standards: AC conductometry