Biogas typically refers to a gas produced by the biological breakdown of organic matter in the absence of oxygen.
The use of biogas technology is an alternative cooking energy for rural people in developing countries.
It provides clean cooking energy, reduces indoor air pollution and reduces the time needed for traditional biomass collection, especially for women and children. The slurry is a clean organic fertilizer that potentially increases agricultural productivity.
Unfortunately, the threat of leaks is a serious problem especially when the quality of materials and labour cannot be guaranteed. However it is relatively cheap and simple to train a local dog to detect the hydrogen sulphide that would be present in any leaks and have it alert someone nearby. Such an animal could easily be trained to carry out regular inspections. The sensitivity of a dog's nose is far greater than commercially available detectors and they can even detect leaks from underground pipes.
On a lighter note - it could also be used to identify anyone that 'passed wind' in a crowded meeting hall enabling the offender to be dealt with appropriately. ;)