The regulations of the German Triathlon Union (DTU) apply. Participation requires full acceptance of these competition rules as well as the DTU's rulebooks.

Here are some key points to note:

Helmet:

• The helmet must be worn and fastened in the transition area before taking the bike off the rack during the swim-to-bike transition.
• During the bike-to-run transition, the bike must be racked before the helmet can be unfastened.

Your transition area:

• Your designated transition spot will be marked with your start number and name.
• At your spot, you’ll find a plastic box. After the swim, all swim equipment must be placed in the box. Similarly, after the bike leg, everything you won’t take on the run must also go into the box.
• You may prepare your transition area by clipping your cycling shoes onto your bike. Running shoes may be placed outside the box on the ground.
• Important: Your transition area is always to the right of your bike. It is limited by the length of your bike: to the left by your bike and to the right by the neighboring bike.
• Please hang your bike by the saddle on the bike rack, with the front wheel facing the aisle.

Transition zone:

• The transition zone is completely fenced off and monitored overnight.
• Bikes may not be covered overnight.

Mounting and dismounting the bike:

• Mounting the bike is only allowed after crossing the mount line outside the transition zone.
• At the end of the bike leg, you must dismount before entering the transition zone and before crossing the dismount line.

Start number:

• The start number must be worn on your back during the bike leg and must be clearly visible from behind.
• During the run, the start number must be worn on your front.

Misconduct:

• Misconduct in the transition area or during transitions may result in penalties by the referees.

Cards:
Referees will show cards to indicate rule violations:

• Yellow: Warning. No penalty. More than two warnings result in disqualification.
• Blue: Time penalty (referee signals with sound, calls out the start number, and shows the blue card). Two time penalties lead to disqualification.
• Red: Disqualification (referee signals with sound, calls out the start number, and shows the red card). Immediate race exclusion.

Time penalties:

• Must be served in the penalty tent in the transition area during the bike leg.
• During the run, penalties are served "on the spot" by stopping immediately.
  • SPRINT: 1 minute
  • OLYMP: 2 minutes
  • CLASSIC: 5 minutes

Drafting:

• Drafting is strictly prohibited on the bike leg for all distances. A minimum distance of 12 meters must be maintained from the cyclist in front.

Electronic devices:

• No electronic devices such as phones, MP3 players, headphones, smart helmets, or similar are allowed during the race.

You can find a more detailed excerpt of the competition rules here.
The latest version of the DTU sports regulations can be found here.