Overview
ISO 8454:2024 specifies a standardized laboratory method for measuring carbon monoxide (CO) in the vapour phase of mainstream cigarette smoke using a non-dispersive infrared (NDIR) analyser. The method applies to vapour-phase samples collected under the machine-smoking regime defined in ISO 4387. It covers apparatus, calibration, sampling, measurement, calculation of CO per cigarette and reporting requirements.
Key topics and technical requirements
- Scope and principle: Measurement of CO in the vapour phase of cigarette smoke collected from routine analytical smoking machines (ISO 3308) and conditioned per ISO 3402.
- Apparatus:
- Conditioning enclosure (ISO 3402) and routine analytical smoking machine (ISO 3308).
- Vapour-phase collection container (gas bag) - impermeability check with 4–6% CO standard; CO concentration must not change by more than 0.2% (volume fraction) over ≥2 h. Typical volumes: ~3 L for 5 cigarettes, ~10 L for 20 cigarettes.
- NDIR analyser calibrated for CO with preferred working range 0–10% CO, sampling rate 0.5–5 L/min. Performance targets: precision 1% FS, linearity 1% FS, repeatability 0.2% FS. Cross-sensitivity limits: response to 10% CO2 or 2% water vapour shall not exceed 0.05% as CO.
- Standard gas mixtures and calibration:
- Use nitrogen as make-up gas; high-purity gases with low CO2 content.
- Calibrate with a high-range standard (e.g., ~5% CO in N2) and verify linearity with at least two lower concentrations (typical: ~1%, ~3%, ~5% CO). Allowed reading ranges: for 5.0% certified gas → 4.8–5.2% observed; for 1.0% → 0.8–1.2% observed.
- Recalibration at least weekly; pre-measure check with high-range gas and full recalibration if deviation > 0.2% (vol.).
- Procedure: Conditioning, NDIR warm-up and zeroing, vapour-phase collection during ISO 4387 smoking, and measurement under consistent temperature/pressure.
- Results and reporting: Calculation of average CO volume and mass per cigarette, with repeatability and reproducibility values updated and test-reporting harmonized with ISO 10315.
- Operational notes: Flameless ignition recommended - lighting technique can significantly influence CO yield.
Applications and users
ISO 8454:2024 is used for:
- Regulatory testing of cigarette emissions.
- Product development and quality control in tobacco manufacturing.
- Analytical laboratories and contract testing facilities performing standardized smoke constituent analysis.
- Research and toxicology studies needing reproducible CO emission data.
Note: Machine-measured emissions are useful for product characterization and regulatory comparison but are not direct measures of human exposure or individual risk.
Related standards
- ISO 4387 - collection of total particulate matter (smoking regime)
- ISO 3308 - routine analytical cigarette-smoking machine
- ISO 3402 - atmosphere for conditioning and testing
- ISO 10315 - harmonized test-reporting requirements
- ISO/TR 19478 - referenced for repeatability/reproducibility data
Keywords: ISO 8454:2024, carbon monoxide, NDIR, cigarette smoke, vapour phase, ISO 4387, calibration, vapour-phase collection container, standard gas mixtures.