<prompt> Bhala okuqhubekayo kwalesi sigaba - Ukukhathala ngenxa yokusebenza ngewashi kuye kwaba nengxenye ezinhlekeleleni eziningana zezimboni, kuhlanganise nenhlekelele yaseThree Mile Island, inhlekelele ye-Space Shuttle Challenger nenhlekelele yaseChernobyl. Umbiko wokugcina weKhomishane Yokugeleza Kwe-Oyili Yase-Alaska ngokuchitheka kukawoyela e-Exxon Valdez  <response>: Umshayeli wemikhumbi wase-United States, u-Earl B. Johnson, wathi kungenzeka ukuthi amahora amaningi okusebenza ayebangela ukukhathala kwabasebenzi, okwenza ukuba umkhumbi ugingqe. 