Gas Sensor for Emergency Workers

In my professional life [Eric] I have used many different gas analyzers for confined space entry as well as emergency response. These units are very expensive and require the user to be able to read the display or be close enough to hear the alert generated if an unsafe condition exists where human entry would need other measures.

I made this to be a very cheap and easily reproduced product which can simply be thrown into any uncertain environment such as a confined space, building with a possible gas leak, fire etc. Any potential entry person can just toss the ball into the area and remotely receive the gas and smoke levels via voice from several hundred meters away.

I used an MQ2 smoke, LPG (Liquified Petroleum Gas), and CO (Carbon Monoxide) sensor. I used freely available code to get the sensor working with an Arduino Nano. Then taking an Ultra Cheap 433MHZ transmitter to output real voice transmit to any basic radio within the area.

This project is fully open-source!

 This section can be used to explain everything about your project.

This project is not only for emergency workers- Every day thousands of people work in industries which expose them to the hazards of “confined space”. The difference between life and death in these areas can be as simple as as a few PPM deviation from standard atmosphere. This project is dedicated and given freely to all of them…

Using the Arduino I was able to easily measure the gas levels. Using the Talkie library I was able to then translate these values into true synthesized human voice (with NO special boards/modules) The transmitter accepts the voice output and directly transmits it out on 433mhz to ANY receiver. It is sending this as an AM transmission- but surprisingly any FM receiver such as scanners/handy talkie radio, EMS radios etc have no trouble receiving the clear voice values.

Then entire package fits nicely into the “ball” form-factor. This enables anyone to throw it a significant distance into a potentially harmful area. No additional equipment required and the best part:

The user never enters the potentially hazardous area whatsoever.

2015 Hackaday Prize Semifinals Video:

Here is a more technical demo:

Video Demo

Updated videos and code walk-through can be found in the links. Further info can also be found in the GitHub repo which includes all the code, design files, PCB layout and design document.

Here is a demo I did on the Adafruit Show and Tell show. Fast forward to 09:46 as the direct link doesn’t seem to work here:

Video covering the basics and full Arduino code walk-through/explanation so anyone can mod the project to suit their needs:

I decided for others to be able to recreate this project easily for themselves- a full video tutorial series would be of great benefit. I know I learn much better from good video versus a static page of instructions so here is the full electronics and PCB step by step assembly tutorial:

Here is the final assembly into the ball and some quick testing/upcoming changes needed:

Upcoming mods on the project will include a higher quality sensor which will likely end up being multiple sensors to more align with industry standard gas analyzers.

Hopefully this project will allow anyone, anywhere to reproduce this tool cheaply and easily anywhere in the world!