No, it isn't dangerous if it's actually abandoned. If you smell any gas, then get the utility to address it properly. Don't go within 20-feet of the line with any open flame.
It depends what state or country you're in as to whether your local fire department gives them out. In most places you'll either need to buy your own or have...
You may have gotten a clog in your evaporation system. This can happen when particles from a dirty gas can become stuck in the system lines. This is the system...