AS 4323.1:2021 Stationary source emissions Method 1: Selection of sampling positions and measurement of velocity in stacks.
This document specifies a method for the selection of sampling positions for obtaining representative samples of pollutants emitted from stacks (including exhaust ducts and other similar outlets), together with a description of the apparatus, procedures and calculations used to measure gas velocity and flowrate.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content constitutes requirements of this document.
NOTE Documents for informative purposes are listed in the Bibliography.
AS 1657, Fixed platforms, walkways, stairways and ladders — Design, construction and installation
AS ISO/IEC 17025, General requirements for the competence of testing and calibration laboratories
AS/NZS 1891.2, Industrial fall-arrest systems and devices, Part 2: Horizontal lifeline and rail systems
AS/NZS 1891.4, Industrial fall-arrest systems and devices, Part 4: Selection, use and maintenance
AS/NZS 3000, Electrical installations (known as the Australian/New Zealand Wiring Rules)
ISO 3966, Measurement offluid flow in closed conduits — Velocity area method using Pitot static tubes
USEPA Method 2F, Determination of stack gas velocity and volumetric flow rate with three-
dimensional probes
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
access hole
hole in the stack at the extremity of a sampling traverse, through which test equipment is inserted
competent person
person who has acquired, through education, training, qualification or experience or a combination of these, the knowledge and skill enabling that person to perform the task required
internal diameter of a circular stack or the hydraulic diameter of a non-circular stack
Note I to entry: The hydraulic diameter is four times the stack internal area divided by the internal perimeter.
differential pressure
difference between the pressures measured at the total and static pressure tappings of a pitot tube. AS 4323.1 pdf download.