ISO 17734-1:2026

Overview

ISO 17734-1:2026 outlines a standardized method for the determination of organic isocyanates in workplace air. Developed by the International Organization for Standardization (ISO), this standard is essential for ensuring accurate monitoring of isocyanate exposure in occupational environments. It specifies the use of derivatization with di-n-butylamine (DBA) followed by liquid chromatography and mass spectrometry (LC-MS) for the analysis of airborne isocyanates. The method is applicable to both the gas and particle phases, covering a wide range of isocyanate compounds, including monofunctional, monomeric diisocyanates, and multifunctional forms such as oligomeric, prepolymeric, and polymeric isocyanates.

Accurate assessment of isocyanates is critical since these compounds are widely used in the production of polyurethane and present significant health risks such as asthma and dermatitis. Due to their high reactivity and sensitisation potential, isocyanates require sensitive and selective analytical approaches for reliable monitoring well below occupational exposure limits.

Key Topics

• Derivatization with DBA: The core of the method involves capturing isocyanates by reacting them immediately during sampling with di-n-butylamine, forming stable derivatives suitable for chromatographic analysis.
• Air Sampling Techniques: The standard covers the use of impingers and glass fibre filters, either singly or in combination, to collect both gaseous and particulate isocyanates from workplace air. It also addresses solvent-free sampling using DBA-impregnated tubes.
• Chromatographic Analysis: After sampling, isocyanate-DBA derivatives are analyzed by high-performance liquid chromatography (HPLC) with mass spectrometric detection (LC-MS). Alternative detection techniques such as chemiluminescent nitrogen detection (LC-CLND) or ultraviolet detection (LC-UV) may also be employed for some compounds.
• Wide Compound Coverage: The method is suitable for a broad range of isocyanates, such as ICA, MIC, EIC, PIC, BIC, PhI, HDI, TDI, MDI, NDI, IPDI, H12MDI, and various multifunctional derivatives.
• Analytical Range: The method is capable of detecting isocyanate levels from approximately 0.2 µg/m³ up to 33 µg/m³, facilitating workplace exposure assessments below regulatory thresholds.

Applications

• Occupational Exposure Monitoring: The primary application is the routine surveillance and assessment of worker exposure to airborne isocyanates in environments such as polyurethane manufacturing, painting, and plastics production.
• Regulatory Compliance: Organizations can use this standard method to demonstrate compliance with national and international workplace air quality regulations concerning isocyanate exposure.
• Industrial Hygiene: The method supports industrial hygienists in identifying sources of isocyanate emissions and designing effective engineering controls or personal protective equipment programs.
• Research and Product Stewardship: Chemical manufacturers and researchers can use the standardized method for product development, studying isocyanate emissions from new materials, or investigating degradation products during thermal breakdown.

Related Standards

• ISO 17734-2: This part of the series details the determination of amines and aminoisocyanates in workplace air, providing complementary methodologies for comprehensive organonitrogen compound monitoring.
• ISO 3696: Specifies the quality of water required for analytical laboratory use, relevant for sample preparation and reagent solutions in the ISO 17734-1 method.
• ISO 5725-2: Addresses repeatability and reproducibility of measurement methods, essential for validating and verifying laboratory analyses.
• ISO 13137: Sets requirements for pumps used for personal sampling of chemical and biological agents, including their suitability for use with the sampling devices described in this standard.

ISO 17734-1:2026 is an indispensable reference for occupational health and safety professionals, laboratory analysts, and regulatory authorities concerned with the safe handling and monitoring of isocyanates in workplace air. By ensuring reliable, sensitive, and reproducible results, compliance with this standard helps to protect worker health and maintain regulatory adherence.