LoRaWAN®
Bathroom Odor Detector
Less Nasty Air. More Attentive Care.
- Detect NH3 & H2S with Higher Accuracy
- Wireless Deployment with up to 3 Years Battery Life
- Support LoRaWAN® & Milesight D2D Simultaneously
- Built-in Buzzer & Traffic Light Indicator for Alarming
Cleaner Bathroom Start with Odor Sensing

Minimalist &
Practical Design
GS301 LoRaWAN® Bathroom Odor Detector is compact in size and easy to install and maintain. With damp proof coating, the detector can work on various conditions of bathrooms.


4-in-1 Sensors with
High-Sensitivity
Integrated with ammonia (NH3), hydrogen sulfide (H2S), temperature and humidity sensors.
Detect ammonia (NH3) and hydrogen sulfide (H2S) gas according to electrochemical principle.
- NH3: ±5% Accuracy
- H2S: ±5% Accuracy
* It is highly recommended that sensors operate below 35°C.
Stay Informed of Foul Air
When ammonia or hydrogen sulfide concentration reaches thresholds, the alarm will be activated, including traffic lights indicator, built-in buzzer and uplink data packets. *Thresholds can be customized


Assistant to Ventilator
for Clearer Air
HVAC system is empowered to automatically adjust based on the detected concentrations of ammonia and hydrogen sulfide produced from the urinal and sewer pipe.
Milesight D2D
Featuring LoRa®
Support Milesight D2D protocol to enable ultra-low latency and direct ventilation control without gateways.
- Lower Latency
- Less than 1 Second Response Time
- Secure Transmission
- Reduce Investment Cost
*When Milesight D2D is enabled, LoRaWAN® protocol can operate as usual.

Smart Restroom Solution
Good restroom experience always has a directly positive impact on occupants’ perception of a building. To make it right and easy, Milesight Smart Restroom Solution provides IoT insights into the status of cleanliness and hygiene.

Multi-Year Battery Operation
GS301 has a battery life of up to 3 years
* Sensor Life can be over 3 Years
**4 x 4000 mAh ER18505 Li-SOCl2 Replaceable Batteries (10 min intervals)
LoRaWAN® Based
- Compatible with Standard LoRaWAN® Gateway
- Penetrate Thick Wall
- 2 km Communication Range in Urban Areas

Milesight IoT Cloud
- Monitoring ambience conditions at any time anywhere
- Interactive collaboration with Milesight IoT sensors to realize scene-based automation
- Android & iOS versions allow you to manage devices at your fingertips
Easy Configuration
Switching on/off and configuring the device via NFC technology from mobile phone or PC
1st Step
Install the Milesight ToolBox
(Android/iOS)
2nd Step
Enable NFC and run ToolBox,
then attach your phone to the device
3rd Step
Verify the password and
start configuring
Flexible Installation
Installation Steps
Specifications | Documents
Wireless Transmission | Protocol | LoRaWAN® , Milesight D2D |
Frequency | CN470/IN865/RU864/EU868/US915/AU915/KR920/AS923-1&2&3&4 | |
Tx Power | 16 dBm (868 MHz)/19 dBm (470 MHz)/22 dBm (915 MHz) | |
Sensitivity | -137dBm | |
Mode | OTAA/ABP Class A | |
Sensors | ||
Ammonia (NH3) | Detection Principle | Solid Polymer Electrochemical |
Range | 0 ~ 10 ppm | |
Accuracy | ± 5% (-40 – 35°C) | |
Long-term Stability | < 1 % accuracy drift per month | |
Resolution | 0.01 ppm | |
Hydrogen Sulfide (H2S) | Detection Principle | Solid Polymer Electrochemical |
Range | 0 ~ 5 ppm | |
Accuracy | ± 5% (-40 – 35°C) | |
Long-term Stability | < 1 % accuracy drift per month | |
Resolution | 0.01 ppm | |
Temperature | Range | -40 – 85°C |
Accuracy | ± 0.2°C | |
Resolution | 0.01°C | |
Humidity | Range | 0 – 100%RH |
Accuracy | ± 2% | |
Resolution | 0.5%RH | |
Others | LED& Buzzer | 1 × Status/Alarm Indicator + 1 × Buzzer |
Button | 1 × Reset/Reboot Button | |
Configuration | Mobile App via NFC | |
Advanced Feature | Milesight D2D Controller | |
Physical Characteristics | Power Supply | 4 x 4000 mAh ER18505 Li-SOCl2 Replaceable Batteries |
Sensor Life | > 3 Years | |
Battery Life | Around 3 Years (10 min interval) | |
Operating Temperature | -40°C – 55°C | |
Relative Humidity | 0% – 95% (non-condensing) | |
Ingress Protection | IP30 | |
Dimension | 120 × 85 × 32.5 mm (4.72 × 3.35 × 1.28 in) | |
Material & Color | PC+ABS (Flame Retardant), White | |
Installation | Wall Mounting |