Due to the slow speeds and grading of sections, trials is quite safe.  That is why we ride in t-shirts and open-face helmets.

Every competition or practice involves riding sections that are graded for the skill-level of the rider.  There are three basic skill levels, though in some regions there are intermediate levels between them:

Trials (also knowns as "footup trials"), is a motorcycle riding discipline where riders attempt to ride a short, technically challenging course without putting their feet on the ground.

Competitions involve riding several short, marked "sections" and tallying the number of times each rider puts their foot down ("dabs").  The sections are marked such that beginners have easier obstacles that require less skill and commitment, while experts need to ride more advanced lines.