Chemical, biotech and research laboratories perform a wide range of applications and tests. Many of these can be impacted by the presence or absence of oxygen, and, thus, require the use of oxygen analysis to measure or monitor oxygen levels.
There are applications and tests that require keeping oxygen at a predetermined level or within a predetermined range so as not to invalidate the results. For example, many procedures require the use of a glove box to maintain a controlled environment. But it is not always understood that oxygen at ambient pressure can diffuse through the pressurized plastic tubing or rubber gloves of the glove box due to Dalton’s Law of Partial Pressures. The unknowing introduction of oxygen may contaminate the research, skew the results and cause the laboratory to incur unnecessary costs to redo the experiment or test.
Some applications require introducing a defined amount or level of oxygen, as written in the Materials & Methods section, through a pressurized gas stream. Given the current norm that the research staff is completely dependent on the manufacturer’s certification of the gas tank, no checks are being performed to verify that those oxygen values are accurate prior to being introduced into the experiment – something that may prove costly if those values are not correct.
Additionally, laboratories need to monitor the oxygen levels of the working environment within their facilities to protect their personnel. This is mostly due to having large stores of inert gas tanks and vessels onsite to support their scientific research. This inadvertently introduces risk that these tanks or vessels may be improperly secured, and, if a leak develops, the inert gas in any of these containers will quickly displace the level of oxygen in the surrounding areas and, unbeknownst to the research staff, immediately create an unsafe and dangerous environment.
AMI offers a complete line of high-performance, industry-leading oxygen analyzers to address each one of these important situations and concerns. Our PPM oxygen analyzers can accurately and reliably detect oxygen levels as low as 0.05ppm to meet your needs for precise trace measurements. Our % oxygen analyzers will help you validate and verify that your higher oxygen concentrations inside controlled environments are within specifications. And last, our oxygen deficiency monitors utilize zirconium-oxide-based technology to help protect your research staff from a dangerous situation if there is a sudden and unexpected drop in the oxygen level inside their working environment. Click on any of the following links to learn more about our products and see how we are a complete solution provider of oxygen analysis.
Hazardous area permanent mount trace oxygen analyzer
Hazardous area portable trace oxygen analyzer
Hazardous area permanent mount percent oxygen analyzer
Hazardous area permanent mount hydrogen sulfide analyzer
Hazardous area portable hydrogen sulfide analyzer
General purpose permanent mount trace oxygen analyzer
General purpose permanent mount trace oxygen analyzer. Atmospheric pressure sample source
General purpose permanent mount percent oxygen analyzer
General purpose permanent mount percent oxygen analyzer. Atmospheric pressure sample source
Multichannel general purpose permanent mount trace oxygen analyzer
Multichannel general purpose permanent mount trace oxygen analyzer for atmospheric pressure samples
Multichannel general purpose permanent mount percent oxygen analyzer
Multichannel general purpose permanent mount percent oxygen analyzer for atmospheric pressure samples
Low cost Division 2 area permanent mount trace oxygen analyzer
General purpose rack mount trace oxygen analyzer
Area safety - permanent mount oxygen deficiency monitor
Area safety – wall mount oxygen deficiency monitor
General purpose percent oxygen probe
Ultra-stable Percent oxygen probe
General purpose rack mount percent oxygen analyzer
Portable Ultra-stable Percent oxygen analyzer
Portable Ultra-stable Percent oxygen analyzer for ambient pressure samples
Portable Ultra-stable Percent oxygen analyzer for aerospace
Conventionally we refer to the fuel-cell type galvanic sensor as “Electrochemical”. It is built using a liquid electrolyte, a noble metal cathode and a lead (typically) anode, and uses a Teflon™ membrane to control the oxygen flow into the active area. Such sensors are comparatively inexpensive, reliable and have been used for many years. They are the only practical way of measuring ppm levels of oxygen, and are also appropriate in many cases for measuring percent levels particularly when measuring in a flammable gas background.
Electrochemical sensors are a disposable part like a flashlight battery. In typical use they last about a year, and require regular calibration. They respond to the partial pressure of oxygen. They are specific to oxygen, and are not affected by the presence of flammable gases. Trace sensors have a zero output in the absence of oxygen, which means that they do not need to have a zero calibration – an almost impossible task in practice. They require no power and are comparatively low in cost. They require temperature compensation which is built into the analyzers that use them but they may respond to a sudden and rapid temperature change. They will also respond to barometric pressure changes in direct proportion to the absolute pressure. These latter characteristics are normally only significant in oxygen deficiency monitoring applications.
Electrochemical sensors should be used in general percentage measurements, in hazardous atmospheres, and with flammable background gases or to measure trace levels of oxygen. For percent measurements in inert background gases such as air, the zirconium oxide sensor is the better choice if power is available.
This kind of sensor uses a ceramic material at high temperature to measure oxygen. This general kind of sensor is commonly used in automobiles to control the air-fuel ratio, but the particular design used for gas analysis is quite different. It has a number of advantages in that it is extremely stable, very long-lived, and immune to barometric and temperature changes. On the other hand zirconium oxide sensors will oxidize anything flammable in the sample stream, burning up any oxygen present while they do so, so that they cannot be used in any gas stream with flammable components, or effectively with ppm levels of oxygen because any slightest trace of anything flammable (such as hydrocarbon gases, carbon monoxide or even oils from your fingers) will eat up trace oxygen giving a falsely low reading.
Zirconium oxide sensors should be used to measure percent levels of oxygen in inert atmospheres, such as the amount of oxygen in the air in an enclosed space. In this application they will last for many years without any real need for calibration or replacement. They should not be used with flammable gases or for measuring ppm levels of oxygen.