Found this on www.cararuns.org and thought it was helpful.

Running Etiquette
While runners are a friendly lot, each one of us still needs to do our part to
keep our paths, roads and trails safe and enjoyable for everyone, including
non-runners. Below are some basic guidelines to adhere to if you’re running
along a multi-use path, trail or on the road as well as some race etiquette.
On the path, trail or road
Especially if you run in high-traffic areas such as Seneca/Cherokee Park,
popular forest preserves in the suburbs, or busy streets:
Always stay to the right unless you are passing someone. Be very careful merging
left into a passing lane. A cyclist, another runner or roller blader could be
passing you and you don’t want to get run over from behind.
Never run more than two abreast when you are with a group. Do not force other
runners, pedestrians or cyclists off of the path. If you are in a particularly
busy area, run single file.
Never stop suddenly in the middle of a run.
Always look both ways—at least twice—before entering or exiting a path, when you
are approaching intersections and at drinking fountains.
Never litter.
Be considerate of those around you and remember that others may be using the
same path, trail or road that you are.
At a race
Do not run in a race if you are not officially registered. It can take away from
the resources of paid participants, create unnecessary traffic and pose
insurance risks. Just don’t do it.
Similarly, unless a race allows it, do not buy another’s bib number and consider
yourself entered. Unless you registered and signed the waiver yourself, you are
not registered.
Line up according to the pace you plan to run. If you are a slower runner,
that's OK, just don’t stand right in the front of the pack.
Follow the instructions of course marshals.
Don’t wear headphones. You reduce your awareness of your surroundings, which is
particularly dangerous in a high-traffic race environment. It may also prevent
you from hearing instructions from course marshals. Many races ban them and will
ask you to remove them prior to entering the race course.
Do not stop suddenly at water tables or if you drop something or if your shoe
comes untied. Move to the side slowly and make sure you do not cut off another
runner. It's OK to walk while you drink your water. Just stay to the side and
carefully merge back with the other runners when you are ready.
It's preferable to leave your cups or other items you may need to discard at a
water station. Never throw trash on someone’s front yard or on more remote areas
of the course.
Use caution and control approaching the finish line. Don’t cut off other runners
and don’t stop suddenly right after crossing the finish line.
Do not bring dogs, strollers, inline skates, bicycles, or other similar items to
a race if the race instructions forbid them. They pose safety hazards to other
participants and may violate insurance coverage. Also, it’s not a great idea to
try to use your cell phone during a race so ask your friends and family to come
out and watch you or call them when you’re done.


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