ISO 10359-2-1994 PDF

Full title and description

Water quality — Determination of fluoride — Part 2: Determination of inorganically bound total fluoride after digestion and distillation (ISO 10359-2:1994). This part of ISO 10359 specifies a laboratory method to determine total fluoride bound in inorganic forms in waters that are heavily contaminated with inorganic constituents, by decomposition/digestion and subsequent distillation, with final measurement by a fluoride-selective technique.

Abstract

ISO 10359-2:1994 defines a procedure for the determination of inorganically bound total fluoride in waste waters and other heavily inorganic-contaminated waters where direct electrode measurement is not suitable. The method involves alkaline treatment and/or digestion, fusion of residues if necessary, steam distillation (using an acid mixture), and quantitative determination of fluoride in the distillate using a fluoride ion‑selective electrode (see also ISO 10359‑1 for electrode measurement principles). The method is intended for samples with fluoride concentrations above about 0.2 mg/l.

General information

• Status: Published / Valid (confirmed as the ISO 10359-2:1994 edition; maintained under periodic review by ISO/TC 147/SC 2).
• Publication date: 20 October 1994 (ISO edition 1, October 1994).
• Publisher: International Organization for Standardization (ISO).
• ICS / categories: 13.060.50 — Examination of water for chemical substances (water quality analytical methods).
• Edition / version: Edition 1 (1994). Confirmed/maintained by ISO review processes (confirmation activity noted in ISO records).
• Number of pages: 7 pages.

Scope

Specifies a laboratory procedure for determining inorganically bound total fluoride after sample digestion and distillation. The method is aimed at waste waters and other waters heavily contaminated with inorganic substances where direct electrochemical (probe) measurement is unsuitable. It covers sample treatment (concentration/evaporation in alkaline medium, fusion or digestion of residues if necessary), steam distillation using an acid mixture (commonly H3PO4/H2SO4), and determination of fluoride concentration in the distillate by a fluoride ion‑selective electrode. The procedure is applicable when the fluoride ion concentration to be measured is greater than about 0.2 mg/l.

Key topics and requirements

• Sample preparation: evaporation/concentration under alkaline conditions and treatment of residues (alkaline fusion or digestion) to release inorganically bound fluoride.
• Distillation: steam distillation (aided by an acid mixture such as phosphoric/sulfuric acid) to separate fluoride from interfering matrix components.
• Measurement: quantitative determination of fluoride in the distillate by fluoride ion‑selective electrode (procedural link to ISO 10359‑1 for electrode technique and calibration).
• Interferences and removal: addresses interferences from cations and boron; distillation and chemical pretreatment are used to eliminate or minimize these interferences.
• Reagents and quality: specifies use of analytical‑grade reagents (e.g., HCl, H3PO4, H2SO4, NaOH), appropriate buffer and calibration procedures for the ion‑selective electrode, and general laboratory QC practices.
• Normative references: cross-references ISO 10359‑1 for electrode measurement principles and ISO 5667‑3 (sampling preservation/handling) where sample handling affects results.

Typical use and users

Used by environmental and public‑health laboratories, wastewater testing facilities, regulatory agencies, industrial process and effluent control labs (for example in chemical, mining, and metal‑finishing sectors), and research groups requiring standardized determination of inorganic‑bound fluoride in heavily contaminated waters. The standard is intended for trained analytical chemists and technicians familiar with sample digestion, distillation apparatus, and ion‑selective electrode techniques.

Related standards

ISO 10359 is a multi‑part standard. Relevant related documents include: - ISO 10359‑1:1992 — Water quality — Determination of fluoride — Part 1: Electrochemical probe method for potable and lightly polluted water (electrode measurement principles and practice). - ISO 5667‑3:1994 — Water quality — Sampling — Part 3: Guidance on the preservation and handling of samples (referenced for sample preservation/handling). National/adopted equivalents (examples): TCVN 6490:1999 (Vietnam adoption of ISO 10359‑2:1994) and other national translations/adoptions and implementation documents.

Keywords

fluoride; water quality; inorganically bound fluoride; digestion; distillation; ion‑selective electrode; wastewater analysis; ISO 10359; analytical method; sampling preservation.

FAQ

Q: What is this standard?

A: ISO 10359‑2:1994 is an International Standard that specifies a laboratory method for determining total fluoride bound in inorganic forms in waters after digestion and distillation, intended for heavily contaminated (waste) waters.

Q: What does it cover?

A: It covers sample treatment (concentration, alkaline fusion/digestion where needed), steam distillation using an acid mixture to isolate fluoride, and quantitative determination of fluoride in the distillate using a fluoride ion‑selective electrode. It also addresses reagents, common interferences (e.g., boron, certain cations) and references sampling guidance.

Q: Who typically uses it?

A: Environmental and wastewater testing laboratories, regulatory agencies, industrial process control laboratories and researchers dealing with effluents and waters where inorganic contaminants prevent direct electrode measurement.

Q: Is it current or superseded?

A: The published edition is ISO 10359‑2:1994 (Edition 1). ISO records indicate the 1994 edition remains the published version and has been subject to ISO periodic review/confirmation activities (ISO metadata show review/confirmation activity in ISO records). Users should consult their national standards body or ISO for the latest confirmation or revision status before relying on it for compliance.

Q: Is it part of a series?

A: Yes — ISO 10359 is in multiple parts. Part 1 covers the electrochemical probe method for potable and lightly polluted water (ISO 10359‑1), and Part 2 covers inorganically bound total fluoride after digestion and distillation (this document).

Q: What are the key keywords?

A: fluoride, inorganically bound fluoride, water quality, distillation, digestion, ion‑selective electrode, wastewater analysis, ISO 10359.