NTSB releases their report (Executive Summary) on the incident of SWA Flt 1380 that resulted in 1 passenger's death and 8 others injured from shrapnel from the engine exploding entering the cabin.
There is a test that engines go through Fan Blade Off Tests (FBO Test). The test is to make sure exploding parts stay inside the engine closure. Which failed in the case of SWA Flt 1380.
What a test looks like: https://youtu.be/wcALjMJbAvU