What are the standards of detection for gas warning devices?
Appearance and functional inspection
Inspect appearance and other items
To detect the appearance of gas detectors and avoid minor issues that may arise during transportation or production assembly, we need to inspect the appearance of the gas detector for defects, cracks, or damage, and check if the entire gas detector component structure is intact. At the same time, check the machine model, label, manufacturer's name, and production time on the body of the gas detector, and verify them one by one with the information provided in the manual or manufacturer to ensure accuracy. At the same time, check the explosion-proof mark, measurement permit mark, and number of this gas detector, which must be complete and clear. Some certificates may require the manufacturer to provide.
2. Power on inspection
The operation of gas detectors requires a power supply, which is usually powered by a built-in battery. We need to turn on the switch and check whether the gas detector is powered on normally. Some gas detectors continue to work by replacing the battery, while others are equipped with a charger. For gas detectors equipped with a charger, we need to test whether the charger is charging properly. When powered on normally, we need to check whether the display screen of the gas detector displays normally.
3. Check if the sound and light alarms of the instrument are normal
For gas detectors with sound and light alarm signals, as they are powered by batteries, when undervoltage is displayed, they should be able to emit sound or light indication signals that are significantly different from the alarm signal.
Indication error
We purchased a gas detector to detect gas concentration. The gas detector cannot display gas concentration accurately, as there may be errors. However, there is a range of these errors, and if they exceed this range, it indicates that the gas detector does not meet the standard. The specified display error varies for different gases. For example, it is normal for the indication error of oxygen to be within ± 0 and 5% VOL.
Alarm error
As we mentioned above, there is also a certain allowable error for the alarm value of a gas detector, as the instrument is affected by various factors and cannot alarm at an accurate concentration every time. Therefore, the alarm concentration is allowed to have an error, as long as the error is within the standard range. The alarm error varies for different gases, for example, the alarm error for oxygen is within ± 0 and 1% VOL.
response time
The response time refers to the time it takes for the gas detector to reach 90% of the stable reading value that the instrument should reach from zero, and this time is also required by standards. This standard, like indication error and alarm error, varies for different gas response times.
Dielectric Strength
For gas detectors, there are also some insulation and voltage resistance standards that must be met. The standard requirements are: at room temperature: ≥ 100M Ω; After humid heat: ≥ 1M Ω. The insulation strength should be able to withstand a 500V AC voltage for 1 minute, and there should be no discharge or breakdown phenomenon. Only when all of these are met can this gas detector meet the standards.
