Overview
EN ISO 15061:2001 - Water quality - Determination of dissolved bromate - Method by liquid chromatography of ions specifies an ion‑chromatographic procedure for measuring dissolved bromate in waters (drinking water, raw/surface water, partially treated water and swimming‑pool water). The method covers sample pretreatment, optional preconcentration, chromatographic separation on anion‑exchange columns, and detection (conductivity with chemical suppression; UV for confirmation). Typical working range is 0.5 µg/l to 1 000 µg/l, with the final procedure and calibration following ISO 8466 guidance.
Key topics and requirements
- Analytical principle: Ion chromatography (anion exchange) with suppressed conductivity detection; UV detection (190–205 nm) as confirmation.
- Scope & matrix: Applicable to various water matrices; pretreatment to remove ozone, solids and reduce interfering ions is required.
- Preconcentration: Use of concentrator (preconcentration) columns or on‑line techniques for low levels; recovery should be within 80–120%.
- Resolution requirement: Peak resolution R between bromate and the nearest peak (usually chloride) must be ≥ 1.3.
- Interferences: Nitrate, chloride, carbonate, sulfate and certain metals can reduce column capacity or interfere with bromate quantification. Organic fouling shortens column life. Matrix clean‑up (e.g., cation exchangers, metal clean‑up columns) and possible standard addition are recommended when interferences are expected.
- Eluents & reagents: Two eluent concentration types (Type 1 for separation; Type 2 for eluting strongly retained ions). Eluents must be degassed and renewed regularly; reagent and stock‑standard preparation (e.g., KBrO3 stock) procedures are specified.
- Quality & calibration: Calibration and method validation per ISO 8466‑1/2; ongoing quality control, replicate analyses and interlaboratory considerations are covered (informative annexes).
Applications and users
- Who uses it: Environmental and public‑health laboratories, drinking‑water utilities, pool water testing services, regulatory agencies, and instrument/column manufacturers.
- Practical uses:
- Routine compliance testing for bromate in treated drinking water (control of disinfection by‑products).
- Monitoring in source waters and distribution systems.
- Method validation and performance checks for laboratories adopting ion chromatography for anion analysis.
- Development/selection of column and eluent combinations to meet resolution and sensitivity requirements.
Related standards
- ISO 3696 - Water for analytical laboratory use
- ISO 5667‑1/2/3 - Water sampling guidance
- ISO 8466‑1/2 - Calibration and evaluation of analytical methods
EN ISO 15061:2001 provides a practical, standardized workflow for reliable bromate determination by ion chromatography, emphasizing preconcentration options, interference control and quality assurance for accurate water‑quality monitoring.