For instance it is known that asthma sufferers, those with cystic fibrosis and some forms of cancer breathe out chemical markers of their condition.
The exhalations of lung cancer victims are known to have higher ethane concentrations than those without the disease.
The hardware could also help asthma sufferers who also breathe out telltale chemicals.
"The sensor will detect traces of special gases and give an early warning to people that an asthma attack might occur in the next three to four hours," he said.
