Significance and Use

Dissolved Ozone is useful in many industries for water sanitization, TOC reduction, food preservation, cleaning-in-place of food and beverage systems, and pyrogen destruction. It is often necessary to know how much ozone has entered the water, how much remains, and the degree to which it has been removed before process use.

Some applications require that contact time, DO ₃ concentration integrated over time, be calculated, to assure disinfection.

Continuous observation of trends in these measurements are needed for continuous quality monitoring and the measurement may be used for closed loop control of ozonation.

In many pure water applications and especially where water quality is regulated by the FDA or similar enforcement agencies, ozone removal must be complete before the water is used. This test method is useful for detecting and determining dissolved ozone levels in water at the trace level as well as at process concentrations where sanitization and chemical reactions occur.

1. Scope

1.1 This test method covers the on-line and in-line determination of dissolved ozone (DO ₃ ) in low conductivity water in the range from 0.001 mg/L to 5.0 mg/L DO ₃ and conductivity < 100 ? S/cm, typical of pharmaceutical and microelectronics pure waters. DO ₃ is detected by correlating the response of a membrane-covered electrochemical sensor to the dissolved ozone concentration.

1.2 This test method provides a more convenient means for continuous measurement than the colorimetric methods typically used for grab sample measurements.

1.3 This test method has the advantage of high sensitivity as well as durability in the process environment and has few interferences.

1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.

1.5 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.

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

D1129 Terminology Relating to Water

D1193 Specification for Reagent Water

D2777 Practice for Determination of Precision and Bias of Applicable Test Methods of Committee D19 on Water

D3370 Practices for Sampling Water from Closed Conduits

Keywords

Ozone; sanitization; dissolved gas; high purity water; pharmaceutical water;

ICS Code

ICS Number Code 17.120.01 (Measurement of fluid flow in general)

DOI: 10.1520/D7677-11

ASTM International is a member of CrossRef.

ASTM D7677