To measure L10 life, engineers run lab evaluations with an accelerated test on every product family. This evaluation can be done with 10 samples run at 100% duty continuously. The standard life of any Sanyo Denki product is 40,000 hours at 60°C while the long life products can go up to 200,000 hours at 60°C. Since it would be impractical to run a 200,000 hour evaluation, the engineers can accelerate the test by testing at higher temperatures. For standard products, the engineers operate the test at 85°C and for long life products, they operate the test at 105°C. In order to pass a fan for this testing, all samples must meet or exceed the life rating. One important item to note, temperature has a drastic impact on the rated life. This should always be considered when comparing life ratings between different fan manufacturers. When comparing different temperature ratings, a good rule of thumb is as follows: for every 15°C of temperature increase, the life will reduce by half.