Once the EII CO has been adjusted to read zero, we recommend that you spray the bump test gas (using the supplied spray tube) into the EII CO dome for 5 seconds. 

The reading on your EII CO should increase to over 5ppm, once you see this reading displayed then you are ready to check your tank. Further instructions on using the bump test gas can be found in the EII CO manual and quick start guide.

Bump test gas (US deliveries 4L, UK & ROW deliveries 5L canisters).

10ppm CO (balance air).

Supplied with red spray nozzel and white spray tube.