Significance and Use

The reactivity and instability of O ₃ precludes the storage of O ₃ concentration standards for any practical length of time, and precludes direct certification of O ₃ concentrations as SRM's. Moreover, there is no available SRM that can be readily and directly adapted to the generation of O ₃ standards analogous to permeation devices and standard gas cylinders for sulfur dioxide and nitrogen oxides. Dynamic generation of O ₃ concentrations is relatively easy with a source of ultraviolet (UV) radiation. However, accurately certifying an O ₃ concentration as a primary standard requires assay of the concentration by a comprehensively specified analytical procedure, which must be performed every time a standard is needed.

The primary UV standard photometers, which are usually used at a fixed location under controlled conditions, are used to certify transfer standards that are then transported to the field sites where the ambient ozone monitors are being used. See Practice D 5110 .

The advantages of this procedure are:

All O ₃ monitors in a given network or region may be traced to a single primary standard.

The primary standard is used at only one location, under controlled conditions.

Transfer standards are more rugged and more easily portable than primary standards.

Transfer standards may be used to intercompare various primary standards.

1. Scope

1.1 These practices describe means for calibrating ambient, workplace or indoor ozone monitors, using transfer standards.

1.2 These practices describe five types of transfer standards:

(A) Analytical instruments

(B) Boric acid potassium iodide (BAKI) manual analytical procedure

(C) Gas phase titration with excess nitric oxide

(D) Gas phase titration with excess ozone

(E) Ozone generator device.

1.3 These practices describe procedures to establish the authority of transfer standards: qualification, certification, and periodic recertification.

1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. See Section 8 for specific precautionary statements.

2. Referenced Documents (purchase separately) The documents listed below are referenced within the subject standard but are not provided as part of the standard.

ASTM Standards

D1071 Test Methods for Volumetric Measurement of Gaseous Fuel Samples

D1193 Specification for Reagent Water

D1356 Terminology Relating to Sampling and Analysis of Atmospheres

D3195 Practice for Rotameter Calibration

D3249 Practice for General Ambient Air Analyzer Procedures

D3631 Test Methods for Measuring Surface Atmospheric Pressure

D5110 Practice for Calibration of Ozone Monitors and Certification of Ozone Transfer Standards Using Ultraviolet Photometry

E591 Practice for Safety and Health Requirements Relating to Occupational Exposure to Ozone

Keywords

boric acid titration; gas phase titration; ozone; primary standard; transfer standard; Calibration--air/atmospheric analysis instruments; Ozone (O 3 ); Photometry; Ultraviolet (UV) analysis--atmospheric applications; Ultraviolet (UV) calibration ;

ICS Code

ICS Number Code 13.040.01 (Air quality in general)

DOI: 10.1520/D5011-92R09

ASTM International is a member of CrossRef.

ASTM D5011