ISO 6145-3-1986 PDF

Full title and description

ISO 6145-3:1986 — Gas analysis — Preparation of calibration gas mixtures — Dynamic volumetric methods — Part 3: Periodic injections into a flowing gas stream. This part of ISO 6145 specifies the periodic-injection technique for producing calibration gas mixtures by injecting discrete volumes of a component gas into a carrier gas flow and describes the calculation principles and practical requirements for preparing calibration mixtures using that technique.

Abstract

This standard defines the dynamic volumetric periodic-injection method used to prepare calibration gas mixtures: it describes equipment arrangements, the principle of calculation (relating injection volume and frequency to resulting concentration), operational conditions (flow, temperature, pressure), and guidance for assessing uncertainty and routine verification. It is a brief technical specification (6 pages) intended to standardize the periodic injection approach within the ISO 6145 series.

General information

• Status: Withdrawn (ISO lists the standard as withdrawn/cancelled).
• Publication date: October 1986 (approved 9 September 1986 in several catalogues).
• Publisher: International Organization for Standardization (ISO).
• ICS / categories: 71.040.40 — Chemical analysis / gas analysis.
• Edition / version: Edition 1 (1986).
• Number of pages: 6 pages.

Scope

ISO 6145-3:1986 is limited to the periodic injection (batch injection into a continuous carrier stream) technique for preparing calibration gas mixtures. It provides the method for determining the resultant volume fraction from the injection frequency and injected volume relative to carrier flow, and gives requirements on apparatus, measurement conditions and calculation of composition and associated uncertainty. It forms part of the ISO 6145 family that collectively describes dynamic volumetric methods for calibration gas preparation.

Key topics and requirements

• Principle of periodic injections: relationship of injection volume and frequency to final gas concentration (volume ratio calculations and formulae).
• Apparatus and configuration: recommended injection devices, flow control and carrier gas arrangements.
• Operational parameters: recommendations on flow rates, temperature and pressure control to minimize errors.
• Calculation and uncertainty: methods to compute composition and to estimate combined uncertainty for prepared mixtures.
• Verification and calibration: guidance for verifying injection volumes/frequencies and traceability to national measurement standards.

Typical use and users

Laboratories and organizations that prepare or use calibration gas mixtures — including metrology institutes, instrument manufacturers, environmental monitoring laboratories, process and emissions testing facilities, and calibration service providers — adopt the periodic-injection technique where intermittent, reproducible injections into a flowing carrier gas offer the required concentration and throughput characteristics.

Related standards

ISO 6145-3 is part of the ISO 6145 series (dynamic volumetric methods for preparation of calibration gas mixtures). Other parts in the series address general methods, volumetric pumps, continuous syringe injection, capillary devices, critical orifices, thermal mass-flow controllers, diffusion, saturation, permeation and electrochemical generation (e.g. ISO 6145-1, ISO 6145-2, ISO 6145-4, etc.). Several parts have been revised since 1986; users should consult the latest parts (for example ISO 6145-1:2019) for current practice.

Keywords

calibration gas mixtures, gas analysis, dynamic volumetric methods, periodic injections, injection frequency, injection volume, carrier gas flow, uncertainty, ISO 6145, ISO/TC 158.

FAQ

Q: What is this standard?

A: ISO 6145-3:1986 is an ISO technical standard that specifies the periodic-injection dynamic volumetric method for preparing calibration gas mixtures by injecting discrete volumes into a flowing carrier gas.

Q: What does it cover?

A: It covers the principle of periodic injections, required apparatus arrangements, calculation of resulting gas composition from injection volume and frequency relative to carrier flow, and guidance on conditions and uncertainty assessment for prepared mixtures.

Q: Who typically uses it?

A: Metrology institutes, calibration laboratories, instrument manufacturers, environmental and emissions testing labs, and others involved in producing or using calibration gas mixtures.

Q: Is it current or superseded?

A: ISO 6145-3:1986 is listed as withdrawn by ISO and national catalogues; the ISO 6145 series has been revised over time and several parts have newer editions — users should refer to the current ISO 6145 parts (and the ISO catalogue) for the latest, active documents. Specific withdrawal records in national catalogues show varying withdrawal/replace dates; consult ISO or your national standards body for authoritative current status.

Q: Is it part of a series?

A: Yes. ISO 6145-3 is part of the ISO 6145 series (dynamic volumetric methods for preparation of calibration gas mixtures), which includes parts addressing methods of calibration, pumps, syringe injection, capillary devices, and other dynamic techniques.

Q: What are the key keywords?

A: Calibration gas, gas mixture preparation, periodic injection, dynamic volumetric, flow metrology, uncertainty, ISO 6145.