- The handheld gas detector has 2 modes of operation: One is passive (diffusion) operation, which means waiting for the gas to explode, the toxic gas or oxygen gas diffuses from the higher concentration area to the set machine area. The second is the operation in the suction mode (integrated self-suction pump).
- This is a simple and common question but requires the following details:
- Most of the sensors used in handheld gas detectors are designed to operate in passive mode. Under these design conditions, the gas is diffused according to the flow of natural air that comes in terms of the sensor, which is accumulated and makes the electrometers of the sensor work. The sensor features will work normally on the appropriate diffusion design of the gas detection machine without suction pumps at all.
- However, there are many who believe that suction pumps are necessary to get gas into the meter and to the sensor at the same time a device with integrated suction pumps will have a wider gas detection range than other simple diffusion measuring devices. That’s really just imaginary, in fact the air flow of the integrated pumps is very small, only a small amount of gas is felt at the end of the straw or right at the beginning of the sampling pump. It must be recognized that the gas detector that operates in diffusion mode or suction pump mode can still only bring the gas detection meter when there is diffused gas to the sensor surface or right at the suction pump input.
- So when exactly should we use the sampling pump? As previously said, the answer is simple. Use suction pumps only with handheld air detectors when it is really necessary to take samples in distant machine conditions with the area to be measured.
- According to the gas regulations in the “restricted space” area, it is necessary to check the area before entering and this inspection clearly needs a sample suction pump to draw gas from that restricted space area to the meter for measurement.
- So the simple rule is that you are at point A and want to measure at point B, you have to use a pump!
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Ventis MX4 gas detection machine with suction pump from Industrial Scientific USA |
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Industrial Scientific USA air sample straw set |
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The Model Ventis MX4 confined space detector kit, industrial scientific, is used to inspect the restricted space area before entering work. These include: Air meters, air suction pumps, straws, calibration instruments, charging accessories, all containers for 1 suitcase for transportation and storage. |
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