There is much discussion and information available about the benefits of using infrared LEL gas sensors. The broad claims include the following advantages:
- The low power needs of these sensors mean they can run from hours to months without needing to recharge the batteries.
- The sensors can operate for years without needing calibration.
- They overcome the limitations of catalytic bead sensors as they are immune to poisoning. Additionally, they can detect combustible gases in oxygen-depleted environments.
And while there can be no denying that these are tangible benefits, there are still some limitations with these sensors. Unfortunately, the limitations can introduce huge risks to the environment. This is especially true if operators are unaware of how the sensor can react under certain conditions.
The Limitations of Low Power Infrared Sensors
The biggest limitation of infrared LEL gas sensors is their inability to detect hydrogen. Under certain conditions, this can be incredibly dangerous. If a user is trying to detect gases in an area where hydrogen may be in the vicinity, it offers no protection. The sensor will not react and will not alert the user.
Manufacturers of these sensors generally acknowledge this limitation. But they identify the cross-interference to hydrogen on the carbon monoxide sensor, which is normally also on the instrument (such as a portable multi gas instrument), as a way to overcome this limitation. Unfortunately, the proposed solution requires the user to employ two sensors as a way to overcome the limitation of low power infrared sensors.
Additionally, the hydrogen interference on carbon monoxide sensors can result in a perceived false alarm. This scenario undermines the user’s trust and confidence in the gas sensor’s results. If it happens repeatedly, users frequently turn the monitor off or opt not to use it. And this can lead to dangerous – even deadly – outcomes. The user has no way of knowing if they are in danger if they can’t trust the sensor.
In addition to being unable to detect hydrogen, these low power infrared sensors are sensitive to many other environmental conditions. Humidity, fog, and ambient light can enter the open chamber. All of these elements can cause interference and result in a false alarm. This limitation creates additional settings in which these sensors cannot be trusted.
The detection capability of the infrared sensor is also limited by the adsorption characteristics of the targeted gas and the bandwidth of the filter in the sensor. Many combustible gases are undetectable by these low power infrared LEL gas sensors. Examples of gases that would be undetectable include:
- Acetylene
- Acrylonitrile
- Aniline
- Carbon disulfide
Yet again, many manufacturers indicate that the solution to these non-detectable gases is the presence of interference detected by the carbon monoxide sensor. But similar to hydrogen, relying on this interference is a risky proposition.
The Importance of Detecting Hydrogen
While low power consumption can be a benefit in the right situations, these infrared sensors introduce risk to the workplace. Their design has many limitations that would result in a failure to alert individuals of the presence of dangerous gases. Most importantly is their inability to detect hydrogen. If there is any chance – at all – that hydrogen is present, workers must be alerted quickly. Even a small leak can turn into a major disaster quickly.
Hydrogen is deadly due to its ability to displace oxygen. It has no odor or taste, meaning people have no mechanism for alerting them of its presence. Asphyxiation can occur quickly in high concentrations. And even at low concentrations, it can cause burns and damage to the respiratory system. The bottom line is that it is simply too risky to leave any room for doubt. You need a reliable sensor that will alert you to all dangerous gases in the proximity. And low power infrared sensors experience many situations where they can deliver a false alarm.
A Reliable Alternative to Low Power Infrared Sensors
Selecting the best sensor for your environment means accounting for all potential dangerous gases that may be present. And while catalytic bead sensors overcome some of the limitations of infrared sensors, they introduce other limitations that are just as dangerous. They can become poisoned when they encounter high flammable gas concentrations. Even common chemicals like silicones, chlorine, or acidic gases, can burn up the sensor.
Even more dangerous, catalytic bead sensors give no warning when their function has been compromised. They appear to be working normally but will fail to alert the user to the presence of dangerous gases. This alternative to low power infrared sensors is less than ideal.
NevadaNano’s MPS™ Sensor Family delivers next-generation, multi-gas accuracy for safe operation. These sensors minimize the likelihood of any negative results or false alarms. They automatically and accurately detect and classify 14 different flammable gases. This goal is achieved with high accuracy, eliminating the need for expensive manual field calibration or reprogramming for different gases.
They can detect hydrogen, which low power infrared sensors are unable to do. And as the world’s first smart flammable gas sensor, they overcome many of the environmental challenges with low power infrared sensors. The MPS sensors provide accurate readings and data even when exposed to rapid temperature and humidity changes. Other sensors, including low power infrared sensors, will fail to work in these environmental conditions.
The new capabilities achieved with the MPS sensors eliminate false alarms, allowing the user to feel confident in the data output. They are also easy and safe for users to deploy in even the most extreme conditions. And the speed in their response time is impressive, averaging under five seconds. This speed can ensure that dangerous conditions are reported sooner. And when every second counts, this speed matters.
These benefits are substantial, and they represent a way to reduce the risks of using low power infrared sensors. In addition to not needing field calibration and a long lifetime, the MPS sensors offer a lower total cost of ownership compared to other sensors. When it matters most, the choice is clear. NevadaNano MPS sensors are the best available technology for detecting all hazardous gases. And this technology can succeed in keeping your workplace safer.