ISO 14403-1:2012 PDF

Overview

ISO 14403-1:2012 specifies a validated laboratory procedure for the determination of total cyanide and free cyanide in water using flow injection analysis (FIA). The standard covers a wide range of water matrices (ground, drinking, surface, leachate, waste water and with adaptations, seawater) and cyanide concentrations from 2 µg/L to 500 µg/L (expressed as cyanide ions). A practical working range described in the document is 20–200 µg/L, adjustable by dilution or changing injection volume.

Key topics and technical requirements

• Analytical principle: automated FIA manifold introduces sample and reagents; cyanide is converted to hydrogen cyanide (HCN), separated by gas-diffusion across a hydrophobic membrane, absorbed in NaOH and detected photometrically.
• Total vs free cyanide:
  • Total cyanide: complex-bound cyanide is decomposed by UV-B irradiation (with a thermoreactor at ~85 °C) prior to diffusion to liberate cyanide from complexes.
  • Free cyanide: UV decomposition is omitted; specific treatments (e.g., tetraethylenepentamine for certain nickel complexes) are described.
• Detection chemistry: absorbed cyanide reacts with chloramine‑T to form cyanogen chloride, which reacts with pyridine‑4‑carboxylic acid and 1,3‑dimethylbarbituric acid to produce a red dye measured by a flow photometer.
• Interferences & sample handling:
  • Oxidizing agents (e.g., free chlorine) degrade cyanide - neutralize with sodium thiosulfate where necessary.
  • Sulfide, sulfite, nitrite, carbonyl compounds and thiocyanate can interfere; procedures (lead carbonate treatment, sulfamic acid in buffer, ethylenediamine addition) are provided.
  • Particulates (>0.1 mm) must be removed to avoid clogging and photometric bias.
• Reagents & calibration: potassium cyanide or potassium tetracyanozincate reference solutions and multi-point calibration (minimum five levels) across the working range; stability and preparation details included.
• Safety: handling and disposal warnings for toxic cyanide compounds.

Applications and users

ISO 14403-1:2012 is intended for:

• Environmental and water quality testing laboratories
• Municipal and industrial wastewater monitoring
• Drinking water utilities and regulators enforcing cyanide limits
• Instrument manufacturers and labs implementing FIA-based cyanide analyzers The method is optimized for high-throughput, automated analysis of multiple samples with reproducible calibration and documented performance characteristics.

Related standards

• ISO 14403-2 (Part 2: continuous flow analysis, CFA)
• Normative references included in the standard: ISO 3696, ISO 5667-3, ISO 8466-1, ISO 8466-2

Keywords: ISO 14403-1:2012, flow injection analysis, FIA, cyanide determination, water quality, total cyanide, free cyanide, gas diffusion, UV decomposition, environmental monitoring.