Hydrogen gas is the smallest and lightest of all known molecules, and its colorless and odorless nature makes it easy to leak. Also, when concentrated above 4% in a confined space, it poses a risk of ignition or explosion.
In order for hydrogen to become a major player in the future energy industry, it is essential to ensure safety via ultra-sensitive gas detection technology across all elements of gas-dealing processes, such as gas production, storage, and transportation. However, conventional gas-leakage sensors using electric signals are prone to yield electrical sparks, which can cause an explosion of leaked hydrogen gas.