carbon monoxide

Carbon monoxide (CO) is an inorganic compound in the air. Under normal conditions, carbon monoxide is a colorless, odorless, tasteless, water-insoluble gas with a melting point of -199 ° C and a boiling point of -191.5 ° C. The gas density is 1.25g/L under standard conditions, and the air density (1.293g/L under standard conditions is very small, which is one of the factors that are prone to gas poisoning. It is a neutral gas. Basic Information Specialist classification: Respiratory examination classification: blood examination Applicable gender: whether men and women apply fasting: not fasting Tips: You can monitor the change of carbon monoxide concentration in the air for 24h or long-term. Normal value Whole blood measurement: 1. Non-smoker HbCO fraction <0.02 (<2% HbCO); 2. The HbCO fraction of the smoker is <0.10 (<10% HbCO). Clinical significance 1. Poisoned HbCO fraction >0.20 (>20% HbCO); 2. The lethal HbCO fraction is >0.50 (>50% HbCO). High results may be diseases: children with carbon monoxide poisoning, hydrogen sulfide poisoning precautions (1) The main components of the oxidant oxidant are manganese oxide and copper oxide. Its function is to oxidize carbon monoxide in the air to carbon dioxide for zero adjustment of the instrument. The oxidizing agent should have an oxidation efficiency of 100% below 100 °C. To ensure its oxidation efficiency, it should be kept dry during use and storage. (2) The main performance indicators of the carbon monoxide infrared gas analyzer are as follows: Measuring range: 0 ~ 30ppm; 0 ~ 100ppm two files. Reproducibility: ≤ ± 0.5% full scale. Zero drift: ≤ ± 2% full scale / 4h. Span drift: ≤ ± 2% full scale / 4h. Linear deviation; ≤ ± 1.5% full scale. Start-up time: 30min. Carbon dioxide interference: 500ppmCO2 ≤ ± 2% full scale. Pumping flow: about 500ml/min. Response time: The pointer indicates 90% of the full scale <15s. (3) Non-test components such as methane, carbon dioxide, and water vapor in the ambient air can affect the measurement results. However, the use of a tandem infrared detector can largely eliminate the interference of the above non-test components. (4) Due to water vapor interference, at the time of measurement. The air sample should be dried by a hose and then entered into the instrument for measurement. (5) The instrument can be continuously measured. The air to be measured is introduced into the instrument with a Teflon tube, and the recorder is connected to monitor the change of the concentration of carbon monoxide in the air for 24 hours or for a long time. (6) After the instrument is started. It must be fully preheated and stabilized for more than 1h. The sample is measured again, otherwise the accuracy of the measurement results is affected. (7) The lower limit of the detection limit of this method is 1 ppm. Inspection process (1) Sample collection: use polyethylene film gas bag, take the scene air to rinse 3 to 4 times, gas collection 500ml, seal the air inlet, bring it back to the laboratory for analysis. It is also possible to bring the instrument to the site for intermittent injection or to continuously measure the concentration of carbon monoxide in the air. (2) Instrument calibration: After the instrument is connected to the power supply, it is stable for 1 h, and the nitrogen or air is introduced into the inlet of the instrument through the Hogarat oxidation tube and the drying tube to perform zero calibration. Connect to the instrument inlet with carbon monoxide standard gas (30 ppm) for end point calibration. Zero and end point calibration should be repeated 2 or 3 times to keep the instrument in normal working condition. (3) Sample measurement: The polyethylene film gas bag containing the air sample is connected to the inlet of the filter containing the color-changing silica gel or anhydrous calcium chloride, and the sample is automatically drawn into the gas chamber. The head indicates the concentration of carbon monoxide (ppm). If the instrument is brought to the field, the concentration of carbon monoxide in the air can be directly measured. If the instrument is connected to a recorder, the concentration of carbon monoxide in the air can be monitored for a long time. Not suitable for the crowd People without signs of carbon monoxide poisoning. Adverse reactions and risks It generally does not cause complications and harm.