Introduction to the Numerical Standards of a Four-in-One Gas Detector
I. Values within different concentration ranges of the combustible gas methane:
Methane (CH4): The gas detector will alarm when the concentration exceeds 1.00%.
When the value of methane (CH4) on the detector is lower than 1.00%, it is considered normal.
When the value of methane (CH4) on the detector exceeds 5%, there is an explosion risk in the presence of an open flame. Electric and gas welding are prohibited.
When the value of methane (CH4) on the detector exceeds 25%, it can cause headache, dizziness, fatigue, inattention, and an acceleration of breathing and heart rate. It is necessary to go outside for fresh air every about 30 minutes.
II. Values within different concentration ranges of carbon monoxide:
Carbon monoxide (CO): The gas detector will alarm when the concentration exceeds 24 ppm.
When the value of carbon monoxide (CO) on the detector exceeds 50 ppm, it is the maximum allowable content for an adult to be exposed to.
When the value of carbon monoxide (CO) on the detector exceeds 200 ppm, after (2 - 3) hours, there will be mild symptoms such as headache, dizziness, and nausea. One should go outside for fresh air every about 30 minutes.
When the value of carbon monoxide (CO) on the detector exceeds 400 ppm, leave the site immediately and report to the relevant responsible person.
III. Values within different concentration ranges of hydrogen sulfide:
Hydrogen sulfide (H2S): The gas detector will alarm when the concentration exceeds 10 ppm.
When the value of hydrogen sulfide (H2S) on the detector is between 50 ppm and 100 ppm, there will be a pungent smell. One should go outside for fresh air every about 30 minutes.
When the value of hydrogen sulfide (H2S) on the detector is between 100 ppm and 200 ppm, the sense of smell will be paralyzed. Leave the site immediately and report to the relevant responsible person.
When the value of hydrogen sulfide (H2S) on the detector exceeds 200 ppm, poisoning will occur within one hour. Leave the site immediately and report to the relevant responsible person.
IV. Values within different concentration ranges of oxygen:
Oxygen (O2): The gas detector will alarm when the concentration is lower than 18.0%.
When the value of oxygen (O2) on the detector is 20.9%, it is the normal content of oxygen in the air.
When the value of oxygen (O2) on the detector is lower than 15%, a person's breathing will become rapid, and they will experience headache, dizziness, general fatigue, and slow movement. Leave the site immediately and report to the relevant responsible person.
