"Check for gas leaks regularly!!! The detectors are less than $20 on Amazon. You can get acclimated to the rotten egg smell they add to make it more noticeable. Whole neighborhoods have been wiped off the map by gas leaks.
Our newly purchased (one-year) home nearly killed me this year. A pocket of leaked natural gas had floated into and sat in our nearby bedroom from the kitchen after I made a whole bunch of stuff for dinner with the gas oven and stove."