Paragraph 8 F1

For measuring CO, CO₂ and HC, the instrument, including the specified gas handling system, must indicate 95 % of the final value as determined with calibration gases within 15 seconds after changing from a gas with zero content, e.g. fresh air. For measuring O₂, the instrument under similar conditions must indicate a value differing less than 0.1 % vol from zero within 60 seconds after changing from fresh air to an oxygen-free gas.