ISO 14966-2019 PDF

Full title and description

St ISO 14966-2019 — Ambient air — Determination of numerical concentration of inorganic fibrous particles — Scanning electron microscopy method. This international standard specifies a standardized procedure using scanning electron microscopy (SEM) combined with energy-dispersive X‑ray analysis (EDXA) to determine and classify the numerical concentration of inorganic fibrous particles (including asbestos varieties and other inorganic fibres) in ambient and indoor air samples collected on track‑etched membrane filters.

Abstract

ISO 14966:2019 describes an SEM/EDXA method for sampling, preparation, identification and counting of inorganic fibrous particles on gold‑coated, capillary‑pore, track‑etched membrane filters. The method defines instrument calibration, counting rules (minimum aspect ratio, length limits), analytical performance, quality control and reporting. It enables discrimination between fibres with compositions consistent with asbestos (serpentine and amphibole), calcium sulfate (gypsum) and other inorganic fibres, and gives guidance on detection limits and the practical range of fibre densities that can be measured on filters.

General information

• Status: Published (International Standard, confirmed)
• Publication date: December 2019
• Publisher: ISO (International Organization for Standardization)
• ICS / categories: 13.040.20 — Ambient atmospheres
• Edition / version: Edition 2 (2019)
• Number of pages: 49

Scope

Specifies a method using scanning electron microscopy for determination of the numerical concentration of inorganic fibrous particles in ambient air and in interior atmospheres (for example, to assess airborne fibres remaining after removal of asbestos‑containing materials). The method covers sampling on capillary‑pore, track‑etched membrane filters, sample preparation (including gold coating and optional plasma ashing), SEM imaging and EDXA composition analysis, fibre counting and classification, calculation of concentrations and estimates of uncertainty, and reporting requirements. The method is optimized for fibres longer than 5 µm and for widths detectable by SEM under the stipulated conditions.

Key topics and requirements

• Sampling media and preparation: use of capillary‑pore, track‑etched membrane filters with gold coating; optional plasma ashing to remove organics prior to SEM.
• Instrumentation and calibration: SEM operational settings, magnification/resolution checks and calibration of EDXA for elemental discrimination.
• Counting and classification rules: fibre defined by minimum aspect ratio (commonly 3:1); fibres counted are typically > 5 µm in length and up to specified maximum lengths; calcium sulfate (gypsum) fibres are identified separately and excluded from asbestos counts.
• Detection limits and range: practical filter counting range approximately 3 to 200 fibres per mm² for fibres > 5 µm under standard conditions; width detection and classification become limited below ~0.2 µm.
• Analytical performance and statistics: calculation of mean fibre concentration, 95% confidence intervals, limit of detection; assessment and reporting of measurement uncertainty.
• Quality assurance and control: instrument checks, counting reproducibility, procedures for early termination of filter evaluation when concentration exceeds set limits, and complete reporting requirements.
• Reporting: specification of sample volume, filter area examined, counted fibre types and sizes, classification results, and associated uncertainty and detection limits.

Typical use and users

Used by environmental and industrial hygiene laboratories, public health and environmental agencies, asbestos survey and remediation contractors, building inspection and indoor‑air specialists, and researchers studying airborne inorganic fibres. Typical applications include ambient air monitoring, post‑remediation verification after asbestos removal, exposure assessment, and research into fibre occurrence and characteristics in indoor and outdoor atmospheres.

Related standards

Closely related to other standards for airborne fibre measurement and microscopy methods, notably standards describing transmission electron microscopy (TEM) methods for asbestos (for example ISO 10312) and national/regional methods (such as VDI guidance documents). ISO 14966:2019 replaces the earlier ISO 14966:2002 edition and sits with other ISO/TC 146/SC 3 publications that address ambient atmosphere sampling and analysis.

Keywords

Ambient air, inorganic fibrous particles, asbestos, scanning electron microscopy, SEM, energy‑dispersive X‑ray analysis, EDXA, track‑etched membrane filter, sampling, counting rules, detection limit, analytical uncertainty, air monitoring, post‑remediation verification.

FAQ

Q: What is this standard?

A: ISO 14966:2019 is an international standard that specifies a scanning electron microscopy (SEM) method, with energy‑dispersive X‑ray analysis (EDXA), to determine the numerical concentration of inorganic fibrous particles in ambient and indoor air.

Q: What does it cover?

A: It covers sample collection on gold‑coated, capillary‑pore, track‑etched membrane filters; sample preparation; SEM imaging and EDXA elemental discrimination; counting and classification rules (e.g., minimum aspect ratio and length thresholds); calculation of concentrations and uncertainties; quality control and reporting.

Q: Who typically uses it?

A: Environmental laboratories, industrial hygiene professionals, public health agencies, asbestos remediation and inspection firms, and researchers assessing airborne inorganic fibres in ambient and indoor environments.

Q: Is it current or superseded?

A: ISO 14966:2019 is the second edition published in December 2019 and supersedes the 2002 edition. According to ISO procedures, standards are reviewed periodically; users should confirm with their national standards body or ISO for any later amendments or replacements.

Q: Is it part of a series?

A: It forms part of the suite of ambient‑air and fibre‑analysis standards maintained by ISO/TC 146/SC 3 and is related to other microscopy and asbestos measurement standards (for example TEM methods such as ISO 10312 and national guidance documents).

Q: What are the key keywords?

A: Ambient air, inorganic fibres, asbestos, SEM, EDXA, track‑etched filter, sampling, fibre counting, detection limit, quality control.