If you wear contact lenses you should remove the contact lenses before going into a tanning bed.
The intense UV rays of the tanning bed can cause the contact lenses to melt and could lead to eye damage as well.
So it's recommended to remove the contact lenses before going into the tanning bed.
Even though in the tanning bed you'll be wearing special tanning bed goggles that can help protect your eyes from the UV rays the contact lenses can still possibly melt from the UV rays.
You could damage the eyes as well as the contact lenses so remove the contact lenses while tanning and then put the contact lenses back in after you're done tanning.