Sparklike devices are used to measure a noble gas (Argon/Krypton, etc.) concentration as a percentage. This data can be used to determine whether an IGU seal has failed. With successive measurements taken from the same IGU, you can quantify gas loss percentage. If rapid loss of gas is detected, it could indicate the hermitic seal of the insulating glass unit has been breached either temporarily or permanently.
Some gas loss in insulating glass units is natural
Insulating glass units have an expected gas loss through permeability that is around 0-1-2% per year. Insulating glass units go through what is known as burst losses, that is when the environmental conditions surrounding the IG forces the gas to vent through the seal, and the seal would then reclose preventing further gas from escaping. The correlation of the measurement to a pass/fail criterion is entirely left to the user to conclude and cannot be made on our behalf.