According to About.com, the use of sunscreen in tanning beds contradicts the whole point of using a tanning bed because it blocks the artificial UV rays that are emitted to create a tan. The artificial UV rays produced by tanning beds are often stronger than those produced by the sun.
Even when using sunscreen, tanning beds are considered unsafe, according to About.com. Using a tanning bed increases the risk of developing skin cancer. The National Cancer Institute says that a person who uses a tanning bed once a month is nearly 55 more times likely to develop melanoma than someone who does not.