SIST EN ISO 20595:2023 PDF

Overview

EN ISO 20595:2022 (identical to ISO 20595:2018) specifies a standardized laboratory method for determining selected highly volatile organic compounds (VOCs) in water using static headspace gas chromatography with mass spectrometric detection (HS‑GC‑MS). The method covers volatile halogenated hydrocarbons and common gasoline components (for example BTXE, TAME, MTBE, ETBE) and is intended for use on drinking water, groundwater, surface water and treated wastewater. It is applicable at mass concentrations greater than 0.1 µg/L (the lower practical limit depends on each compound, blank values and matrix effects).

Key Topics and Requirements

• Analytical principle: static headspace sampling coupled to GC‑MS (HS‑GC‑MS) for selective VOC determination.
• Target compounds: listed in Table 1 of the standard - examples include benzene, chlorobenzenes, chlorotoluenes, brominated methanes and various gasoline-related compounds.
• Performance range: applicable to concentrations >0.1 µg/L; lower limits are compound- and matrix-dependent.
• Quality controls: blank value control and full-procedure controls to monitor contamination, recovery and method integrity.
• Identification & quantification: mass spectrometric identification criteria and calibration procedures, including use of internal standards.
• Procedure elements covered: reagents, apparatus, sampling, sample preparation, GC‑MS operating conditions, calibration, evaluation, expression of results and test reporting.
• Supplementary guidance: annexes provide examples of GC columns, headspace vials/septa, internal standards, headspace/GC conditions and performance data.

Applications and Users

This standard is intended for laboratories and organizations involved in environmental and public‑health water monitoring where accurate quantification of volatile organics is required:

• Drinking water utilities verifying compliance and contamination investigations
• Environmental testing laboratories performing routine VOC surveillance of surface water and groundwater
• Wastewater treatment facilities monitoring residual volatile organics in treated effluent
• Environmental consultants and regulators assessing pollution incidents and remediation outcomes
• Research groups studying VOC fate and transport in aquatic systems

Adoption of EN ISO 20595:2022 supports consistent, comparable HS‑GC‑MS VOC data across labs and jurisdictions.

Related Standards

EN ISO 20595 was developed under ISO/TC 147 (Water quality). Laboratories should integrate this method with their quality management and relevant national water‑sampling and reporting standards to ensure compliant sampling, chain of custody and data reporting for VOCs in water.