ISO 27368:2008

Overview

ISO 27368:2008 is an International Standard from ISO that specifies analytical methods for detecting two primary asphyxiant toxicants-carbon monoxide (CO) and hydrogen cyanide (HCN)-in blood samples collected from fire casualties. In blood, CO is measured as carboxyhaemoglobin (COHb) and HCN as cyanide ion (CN−). These gases are major contributors to the toxic effects of smoke inhalation during fires, and their accurate detection is crucial for forensic analysis, emergency medicine, and fire safety research.

This standard outlines trusted, well-established laboratory procedures for analyzing both ante-mortem and post-mortem blood samples. It takes into account analytical factors such as robustness, repeatability, reproducibility, effectiveness, and the types of instruments suitable for these analyses. Recommendations for sample collection, storage, analysis, and quality control are also included, ensuring the integrity and reliability of results.

Key Topics

• Sample Collection and Handling

  • Guidance on collecting blood from fire victims, focusing on minimizing degradation and gas loss.
  • Instructions on suitable sample containers, preferred blood tube additives (e.g., heparin, potassium oxalate), and recommended storage conditions to preserve CO and HCN content.
  • Special considerations for handling ante-mortem, post-mortem, and burned (solid) blood samples, including homogenization of clotted or burned samples.

• Analytical Methods

  • Methods for measuring CO in blood as carboxyhaemoglobin (COHb), utilizing technologies such as oximeters, spectrophotometry, and gas chromatography.
  • Techniques for determining HCN as cyanide ion (CN−) in blood, including colorimetric analysis, spectrophotometry, gas chromatography, and high-performance liquid chromatography (HPLC).
  • Evaluation criteria: analytical principle, analysis time, repeatability, reproducibility, and suitability for different sample qualities.

• Quality Assurance

  • Use of controls and calibrators, including negative and positive blind controls, to ensure accuracy and reliability of results.
  • Recommendations for duplicate testing and confirmatory analyses using alternative methods when possible.
  • Criteria for reporting results and ensuring robust data interpretation.

Applications

• Forensic Toxicology
  ISO 27368:2008 provides tools for accurate forensic investigation of fire-related injuries and deaths, helping to determine the cause and manner of death by quantifying blood levels of CO and HCN.

• Emergency Medicine and Clinical Toxicology
  Enables rapid assessment of fire victims exposed to smoke, supporting diagnosis and immediate treatment for smoke inhalation injuries and asphyxiant poisoning.

• Fire Safety Research and Regulation
  Assists researchers and regulatory bodies in assessing the toxic danger of building materials and fire environments by linking atmospheric measurements with actual blood toxicant levels.

• Public Health and Statistical Analysis
  Provides standardized data for fire statistics, contributing to the development of fire safety standards, regulatory policy, and improvements in building material selection and emergency response planning.

Related Standards

The methods and principles outlined in ISO 27368:2008 are closely linked to several important standards in fire safety and analytical chemistry, including:

• ISO 19701: Methods for sampling and analysis of fire effluents
• ISO 13344: Estimation of the lethal toxic potency of fire effluents
• ISO/TS 13571: Life-threatening components of fire – Guidelines for estimation of time available for escape
• ISO 13943: Fire safety vocabulary
• ISO 3696: Water for analytical laboratory use – Specification and test methods

These related standards support comprehensive approaches to fire safety, analytical best practices, and terminology consistency.

Keywords: ISO 27368:2008, blood analysis, carbon monoxide, hydrogen cyanide, COHb, CN-, forensic toxicology, fire victims, smoke inhalation, asphyxiant toxicants, analytical methods, emergency medicine, fire safety standards.