Have you ever encountered a situation where a newly purchased gas alarm becomes unresponsive after using it for a short period of time, or frequently gives false alarms? You may not expect that the culprit is not poor equipment quality, but rather sensor "poisoning". This is not a joke, sensors can really be 'poisoned', and this' poison 'often comes from things that are very common in your workshop.

1、 Can sensors also be 'poisoned'?

Yes, this is not a metaphor, but a physical and chemical phenomenon that actually occurs.

What is sensor 'poisoning'?
Simply put, it means that the sensitive components inside the sensor are "contaminated" by certain chemicals, causing it to lose its original activity, just like how people get sick after taking poison.

What are the consequences?

• The sensor becomes' sluggish ', and when gas leaks, its response is slow or even unresponsive

• The readings are becoming increasingly inaccurate, so do not sound an alarm when it is necessary

• Or conversely, calling the police without reason

The scariest thing is that this kind of 'poisoning' is oftenirreversibleIn other words, the sensors that have been poisoned are basically scrapped and can only be replaced with new ones.

2、 Who is most susceptible to 'poisoning'?

The most susceptible to "poisoning" isCatalytic combustion sensorThat is, the type used to detect flammable gases.

Why it? Because its working principle is to allow combustible gases to "burn on a small scale" under the action of a catalyst, and to measure concentration through temperature changes. And some chemicals can act like "toxic drugs", destroying this catalyst and rendering it ineffective.

3、 What are 'poisonous drugs'?

In the factory workshop, these common substances are the "natural enemies" of catalytic combustion sensors:

1. Silicon compounds

• Where to hide:Silicone sealant, silicone grease lubricant, silicone oil, certain cleaning agents, cosmetics, hair gel

• Common scenarios:Sealing glue used during equipment maintenance, moisture-proof silicone in electrical cabinets, and hand cream on workers' hands

• Hazard level:★★★★★ (The most toxic, a little contact may render the sensor useless)

2. Sulfur containing compounds

• Where to hide:Hydrogen sulfide (source of odor in sewage treatment plants), carbon disulfide, and certain lubricant additives

• Common scenarios:Sewage treatment plant, petrochemical plant, rubber processing workshop

• Hazard level:★★★★☆

3. Halogen containing compounds

• Where to hide:Chlorine gas, Freon refrigerants, certain cleaning agents (chlorinated hydrocarbons)

• Common scenarios:Cleaning processes for refrigeration rooms, chemical plants, and electronic plants

• Hazard level:★★★★☆

4. Lead containing compounds

• Where to hide:Lead containing gasoline, certain paints, solder fumes

• Common scenarios:Old vehicle exhaust and welding operations

• Hazard level:★★★☆☆

4、 How to prevent sensor poisoning?

Since poisoning is so scary, what can we do?

1. Think carefully during installation

• Do not install the alarm in a location that may come into contact with these "toxins"

• For example, stay away from repair areas that use silicone sealant

• Stay away from equipment that may contain silicone oil vapor (such as vacuum pump exhaust ports)

2. Pay attention to protection during homework

• If silicone sealant or lubricant must be used near the alarm, temporarily move or shield the alarm first

• After completing the homework, ensure adequate ventilation before restoring the alarm function

3. Choose the appropriate sensor

• If these "toxins" are inevitably present in your environment, you may consider usinginfrared sensorAlternative catalytic combustion sensor

• Infrared sensors are not afraid of these chemicals and have a longer lifespan, but the price will be higher

4. Regular testing and verification

• Regularly use standard test gases to verify whether the alarm can still respond normally

• If you notice a significant slowdown in reaction or a decrease in sensitivity, you should suspect whether you have been poisoned

5、 Can electrochemical sensors also be 'poisoned'?

Electrochemical sensors (for detecting toxic gases and oxygen) are relatively more resistant to "toxicity", but they are not immune to all kinds of toxins.

Its problems are more about "interference" and "saturation":

• Interference:Some other gases can also cause reactions in electrochemical sensors, leading to false alarms

• Saturation:Exposure to high concentration target gas for too long can cause the sensor to become 'exhausted' and unable to recover

So, for electrochemical sensors, it is also important to avoid long-term exposure to high concentration gas environments.

Summary: Remember these points

1. Sensors can really be 'poisoned'Especially catalytic combustion type (measuring combustible gas)

2. Silicone, sulfur-containing substances, chlorine containing cleaning agentsIt is a common "poison drug"

3. Irreversible poisoningOnly the sensor can be replaced

4. Prevention is the best wayAvoid pollution sources, use infrared sensors, and conduct regular testing

One sentence suggestion:
If you frequently use silicone sealant, chlorine containing cleaning agents, or have hydrogen sulfide in your workshop, please pay special attention to your combustible gas alarm and consider upgrading it to an infrared sensor or increasing the testing frequency to prevent "poisoned" sensors from becoming safety hazards.

Safety is no small matter, only by understanding these 'invisible killers' can your alarm truly stand up.