If your gas detector Cuby Protect shows 50% in the app, but the alarm does not sound, you are probably confused. And that is completely normal.
The good news: your device is working correctly.
The most common confusion we see is this:
“I set my alarm to 10%”
“The app shows 50%”
“Why doesn’t it sound if it already passed 10%?”
To understand why this is not a problem, you first need to know what your detector is actually measuring.
LEL stands for Lower Explosive Limit. It is a safety concept that answers this question: How much gas needs to be present in the air for there to be a risk of ignition if a spark appears?
In simple terms:
The LEL is the critical point from which a gas concentration could ignite if there is a spark, flame, or another heat source. Before reaching that point, even if gas is present, there is no explosion risk.
Because it is an international safety standard.
Detectors do not measure “how much gas there is” in an arbitrary way. They measure how close the gas level is to the critical point (LEL).
This allows:
Having a consistent scientific reference
Comparing danger levels objectively
Configuring early alarms in an intelligent way
The percentage you see in the Cuby app is NOT how much gas there is in the air. It shows how close you are to the alert threshold you configured.
It is a “progress bar” toward your alert point.
You configured Cuby Protect to trigger an alert at 10% of the LEL:
| What the app shows |
Real meaning | Does the alarm sound? |
| 25% | You are at 2.5% of the LEL (25% of the way toward your 10% LEL threshold) | ❌ No |
| 50% | You are at 5% of the LEL (50% of the way toward your 10% LEL threshold) | ❌ No |
| 75% | You are at 7.5% of the LEL (75% of the way toward your 10% LEL threshold) | ❌ No |
| 100% | You reached your threshold: 10% of the LEL | ✅ SÍ |
The alarm is activated when it reaches 100% and remains at that level for at least 20 seconds. This helps prevent false alarms caused by momentary spikes.
If you configured it at 10% of the LEL:
0% in the app = No detectable gas
50% in the app = Gas is present, you are at 5% of the LEL (half of 10%)
100% in the app = You reached 10% of the LEL → Cuby Protect sends an alert via WhatsApp and a phone call
Setting Cuby Protect to 10% of the LEL is a standard safety practice because:
✔ It is a real early warning
It alerts you well before any risk exists
You are still far from the critical point
✔ It gives you time to act calmly
You can ventilate the space
Locate the source
Make decisions without pressure
✔ It prevents false alarms
Small, momentary concentrations do not trigger the alarm
It only alerts when there is a sustained upward trend
✔ It is the international standard
Complies with safety regulations
Recommended by manufacturers and experts
To properly use your Cuby Protect alarm:
Configuration:
Keep the threshold between 5% and 10% of the LEL
Do not set it higher (you would lose the early warning advantage)
If you see percentages in the app:
Below 50%: Minimal gas presence, just monitor
Between 50–80%: Consider ventilating the space
Above 80%: Ventilate immediately and locate the source
100%: The alarm sounds, act according to the safety protocol
The percentage shown by Cuby Protect is a “progress bar” toward your alert threshold, not the actual percentage of gas in the environment.
To remember:
The LEL is the critical safety point
The app shows how close you are to the configured 10%
The alarm sounds at 100% in the app = 10% of the LEL
If your detector shows 50% but does not sound, it is doing exactly what it should: continuously monitoring and alerting you only when you reach the configured level.
Important: If that percentage remains constant and does not go down, even if it has not reached 100%, you should ventilate and inspect immediately. A persistent percentage may indicate an active leak and, even below the explosive threshold, prolonged exposure to gas can represent a risk of intoxication.
The Cuby Protect gas and carbon monoxide alarm is designed to warn you well before the situation becomes dangerous. However, if you smell gas, do not wait for the alarm to sound: ventilate, inspect, and act immediately. The human sense of smell can detect LP gas at very low concentrations.
It is not just a gas detector. It is an intelligent prevention system that keeps you informed without generating unnecessary alarms, while also giving you the tools to act in time when you truly need to.