ISO TS 12869-2-2024 PDF

Full title and description

Water quality — Detection and quantification of Legionella spp. and/or Legionella pneumophila by concentration and genic amplification by quantitative polymerase chain reaction (qPCR) — Part 2: On-site methods. This technical specification sets out requirements and performance characteristics for on-site/field qPCR systems that detect and quantify Legionella spp. and L. pneumophila in water samples, with the aim of ensuring reliable, reproducible results outside the conventional laboratory environment.

Abstract

This document provides guidelines, minimum requirements and performance characteristics for manufactured systems intended for on-site detection and quantification of Legionella spp. and L. pneumophila using qPCR. It specifies general methodological requirements, performance evaluation and quality-control requirements for on-site technologies and is intended to be used by manufacturers and end users to ensure safe and effective operation. Results are expressed as genome units per millilitre (or litre). The specification notes limitations where suspended matter, background microorganisms or water-treatment additives interfere with method sensitivity, and it clarifies that conventional qPCR does not indicate physiological state (viability) of detected organisms unless additional procedures are used.

General information

• Status: Published.
• Publication date: 5 April 2024 (published April 2024).
• Publisher: International Organization for Standardization (ISO).
• ICS / categories: 07.100.20 (Microbiology of water).
• Edition / version: Edition 1 (Technical Specification, 2024).
• Number of pages: 25.

Scope

The scope covers on-site/field methods for concentration, genetic amplification and quantitative detection of Legionella spp. and L. pneumophila in all types of water (for example hot and cold water systems, cooling tower water), except where suspended solids or high background microbial loads adversely affect detection or quantification. It sets out methodological, performance evaluation and quality-control requirements for on-site qPCR technologies so manufacturers can deliver systems that provide reliable field results and end users can operate them following manufacturer instructions and appropriate controls. For validation and specific performance requirements the document refers to the clauses within the specification.

Key topics and requirements

• Requirements for on-site qPCR systems: general methodology, instrumentation and consumables designed for field use.
• Sample concentration and DNA extraction approaches suitable for portable workflows.
• Performance evaluation: limits of detection and quantification, calibration/standard curve verification, recovery assessment and measurement uncertainty.
• Quality control and routine controls to be run on-site to ensure assay validity and reproducibility.
• Applicability notes and interference: effects of suspended matter, background microorganisms and some water-treatment chemicals on sensitivity and quantification.
• Statement on detection vs viability: qPCR reports genome units and does not by itself determine physiological state unless combined with specific pre-treatments or adjunct methods.

Typical use and users

This technical specification is intended for manufacturers of on-site qPCR detection systems and for end users who operate field detection equipment, including environmental testing companies, water utility field teams, building and facilities managers, public-health investigators, and occupational hygiene practitioners who need rapid, on-site screening for Legionella contamination. It is also used by regulatory and conformity-assessment bodies when assessing field-deployable Legionella testing solutions.

Related standards

Closely related documents include the foundational ISO/TS 12869 series covering qPCR detection and quantification of Legionella (the earlier ISO/TS 12869 document describes laboratory-based qPCR methods and methodological requirements), and other ISO guidance and standards on validation and performance characteristics of quantitative microbiological methods (for example documents produced by ISO/TC 147/SC 4). Users should consult the broader ISO/TC 147/SC 4 work for companion standards on validation, method equivalence and microbiological testing practices.

Keywords

Legionella, Legionella pneumophila, qPCR, on-site methods, field testing, water quality, detection, quantification, genome units, sample concentration, DNA extraction, performance characteristics.

FAQ

Q: What is this standard?

A: ISO/TS 12869-2:2024 is an ISO technical specification that defines requirements and performance criteria for on-site (field) qPCR methods and systems used to detect and quantify Legionella spp. and L. pneumophila in water samples.

Q: What does it cover?

A: It covers methodological requirements for concentration, genic amplification by quantitative PCR, performance evaluation (limits of detection/quantification, calibration), and quality-control measures specific to on-site systems, and it explains applicability and limitations in different water matrices.

Q: Who typically uses it?

A: Manufacturers of portable/field qPCR systems, environmental testing teams, water utilities, public-health and regulatory agencies, facility managers and field technicians responsible for Legionella monitoring and rapid screening.

Q: Is it current or superseded?

A: ISO/TS 12869-2:2024 is published and current as of April 2024. Users should check the ISO catalogue or their national standards body for any subsequent amendments or updates.

Q: Is it part of a series?

A: Yes — it is Part 2 of the ISO/TS 12869 work on qPCR-based detection and quantification of Legionella. Part 1 / earlier ISO/TS 12869 documents cover laboratory-based qPCR methodologies and related methodological requirements.

Q: What are the key keywords?

A: Legionella, Legionella pneumophila, qPCR, on-site testing, field methods, water quality, detection, quantification, genome units, sample concentration, DNA extraction.