Portable Toxic Gas detector Introduction Series – Part 5 (End)
- In this series, we have a look at the gas detector, the division of toxic gas detectors, the operational structure of some types of toxic gas sensors. This section presents the issue of calibration, bump test of toxic gas detectors. The issue of in-depth research of sensor technologies, methods of measuring each type of toxic gas, conducting the selection of a truly suitable toxic gas detector both technically and economically, please do not mention here. We will proceed to introduce these issues through other articles.
Part 5 – Calibration, Bump test…
- All toxic gas detectors need to be tested according to a schedule. In two types of fixed gas measuring systems and handheld gas detectors, handheld gas detectors need to be calibration more frequently due to frequent changes in the environment in which they are exposed.
- A typical calibration schedule for fixed gas measurement systems can be quarterly, semi-annual or even a whole year with good systems.
- A typical calibration schedule for handheld gas detectors is a daily “bump test” contact test and a monthly calibration schedule. Almost all handheld gas detectors require a specific calibration sample gas pre-supplied by the manufacturer.
- Because a gas detector is used for the safety of workers, it is very important to ensure it is working in accordance with the specifications given by the manufacturer.
- Specific standards in Australia show that an operating person of any type of gas detector should check the performance of the gas detectors every day and it is calibration and used in accordance with the manufacturer’s instructions and warnings.
- A “bump test” test involves the exposure of a gas detector to a known concentration of gas to ensure that the gas detector will respond and functions such as sound alerts, images are confirmed to work well. It is also an important test for handheld gas detectors to ensure it does not experience any accidental or intentional damage. By checking the case and fasteners are intact to ensure that any liquid or dirt can get into the gas detector.
- The calibration kit or basic test will include calibration gas, exhaust regulating valve, calibration cap, connector (usually supplied with gas detector) and a box for storage and transportation.
- Since one of the 2500 400 400 700 devices will fail to respond to hazardous gas concentrations, many large enterprises use an automated calibration station to test and calibration their gas detectors daily.
O2 gas concentration
- Monitoring the shortage of O2 gas concentrations is used to ensure the safety of workers. Frozen substances such as Liquid Nitrogen, Liquid Helium, Liquid Argon are inert gases and can replace O2 in enclosed spaces if leakage appears.
- The deterioration of O2 levels can bring a very dangerous environment for workers, who may not pay attention to this problem until they suddenly lose consciousness.
- With this problem in mind, an O2 gas concentration meter is especially important to quickly detect when the leakage of hazardous substances occurs in the environment.
- Typical applications of O2 gas detectors are laboratories, MRI labs, pharmaceuticals, semiconductors, and frozen suppliers.
Hydrocarbons and organic compounds
- Detection of hydrocarbons can be based on a mix of hydrocarbon gases, or other volatile organic compounds and sensor materials integrated in the sensor.
- The selection and sensitivity depends on the molecular structure and concentration of organic compounds. However, it is difficult to design a sensor for a separate VOC gas. Many VOC detection sensors use the fuel-cell method.
- Voc compounds in the environment or atmosphere can be determined based on different principles of operation and different interactions of organic compounds and components of sensors. There are electronic devices that can detect the concentration of the millionth despite not being specially selected.
- Others can predict with reasonable accuracy the molecular structure of volatile organic compounds in the environment or ambient atmosphere and can be used as precision gauges of chemical fingerprints and, moreover, health trackers
- Ammonia gas is constantly monitored during industrial refrigeration and biodegradable processes, including breathing. Depending on the necessary sensitivity, different types of sensors are used (For example, ionization of flame detection, semiconductor, electricity, photonthtrosy film. This detection machine usually operates near the Explosive Limit below 25 ppm; However, Ammonia detection for industrial safety requires continuous monitoring above the fatal exposure limit of 0.1%
- The operation of a handheld gas detector or fixed toxic gas detector system is related to many technical issues, many safety standards, and should be consulted selected by individuals with expertise, experience and enthusiasm.
- To be able to choose a machine that is suitable both technically and economically, please contact TES Industry’s consultant for advice and answers on all issues related to gas measurement and gas detection.
by TES Industry