Gas work is permitted work and it is pressure tested before anything is put back into service. If you smell gas, leave the building and call the utility from outside before calling anyone else.
The common jobs are running a line to a new appliance, repairing a line found leaking during a service, and replacing older black iron that has corroded at the threads. Each is straightforward when done properly and dangerous when it is not.
Corrosion at threaded joints is the usual failure point on older Wichita installations, particularly where a line runs through a crawl space or against an exterior wall.
Technician insight
If you smell gas, do not operate a light switch or a phone inside the building. Leave first, then call the utility from outside.