Overview
EN ISO 7012-3:2025 - Paints and varnishes: Determination of preservatives in water-dilutable coating materials - Part 3: Determination of in‑can isothiazolinones with LC‑UV and LC‑MS - is a CEN-adopted ISO standard that specifies apparatus and analytical methods for measuring in‑can isothiazolinone preservatives in water‑dilutable coatings and related products (including polymer dispersions). Published in 2025, this method provides laboratory procedures for reliable quantification using liquid chromatography with UV detection and mass spectrometric detection.
Key topics and technical requirements
- Scope and applicability: Methods tailored to water‑dilutable coating materials and polymer dispersions; focuses on in‑can (container) preservatives.
- Apparatus and equipment: Requirements for extraction and sample preparation devices, LC‑UV/VIS systems, and LC‑MS or LC‑MS/MS instruments.
- Sampling and sample prep: Guidance on representative sampling, homogenization and extraction procedures to ensure accurate preservative recovery.
- Analytical procedures:
- Extraction workflows for LC‑UV and LC‑MS analyses.
- Operation conditions for LC‑UV and LC‑MS (examples provided in annexes).
- Filtration, dilution and blank-handling steps.
- Calibration and quantification: Procedures for preparing calibration standards, dealing with matrix effects (including a standard‑addition option in the normative annex), and guidelines for calibration by LC‑UV and LC‑MS.
- Quality control: Addressing interferences, blank checks, precision assessment (repeatability and reproducibility limits), and reporting requirements.
- Annexes: Informative examples of LC conditions, multiple reaction monitoring (MRM) LC‑MS/MS settings, calculation methods for standard addition, homogenization/extraction techniques, and interlaboratory test results.
Practical applications
- Quality control (QC): Routine verification of preservative concentration in production batches to maintain product stability and shelf life.
- Regulatory compliance: Evidence of preservative levels for product safety, labeling and regulatory reporting.
- Formulation development and R&D: Assessing preservative efficacy and interactions in new water‑borne paint and varnish formulations.
- Contract and third‑party testing labs: Standardized test methods for reliable, comparable results across laboratories.
Who should use this standard
- Coatings manufacturers and formulators
- Industrial and commercial QC laboratories
- Analytical chemists using LC‑UV or LC‑MS techniques
- Regulatory affairs and compliance teams
- Accreditation bodies and interlaboratory study coordinators
Related standards
- ISO 1513 - Examination and preparation of test samples
- ISO 3696 - Water for analytical laboratory use
- ISO 15528 - Sampling for paints, varnishes and raw materials
Keywords: paints and varnishes, isothiazolinones, in‑can preservatives, LC‑UV, LC‑MS, water‑dilutable coating materials, polymer dispersions, analytical methods, ISO 7012‑3:2025.