Natural Gas Has No Odor
The odor that you recognize as natural gas is added to natural gas by the utility company.  That odorant, mercaptan can be scrubbed out as the gas passes through sand or dirt.  It can even be removed as gas passes through a new steel gas pipe until the pipe becomes saturate with it.  Once that happens, the odorant will no longer be removed.  Why is this important?

Gas leaking from an underground gas leak can seep into structures without the normal or with a reduced gas odor.  You might not be able to smell it.  This knowledge should explain why you cannot and should not investigate a reported gas leak without your combustible gas meter.

Gas can trick a carbon monoxide alarm

Bring your gas monitor with you when you investigate sounding carbon monoxide alarms.  You need not only your CO monitor,  you also need your gas meter.   CO alarms can be triggered by natural gas.  If the odorant has been scrubbed out of the gas, you would think that the CO alarm was defective, and might leave a hazardous condition in in the home when you take up from the  "unwarranted" CO response. 

Step Potential

A downed high voltage wire that is live, can electrify the ground.  As the distance from the wire increases the electric potential present diminishes.  If you could see it, it would look like ripples in a pond expanding away from a rock thrown in to the water.  A person walking towards the wire could have each foot at a different electrical potential as he steps forward.  The result would be the passing of electrical current up on leg ad down the other to the detriment of the person.  Depending on a number of variables, this could be deadly for him.  Do not approach a downed electrical wire.  If you find yourself close to a high voltage wire, hop or shuffle away from the wire while keeping your feet close together.  This will prevent you from straddling two different electric potential zones.