Each of those trucks should belong to a company and the wise thing for company to do is to insure its assets. So I believe petroleum marketers should have some form of business insurance on all their assets be it building, tank farms, storage facilities and petroleum tankers. I wouldn't even be surprised to hear they also insure their workers and engineers. There are various reputable insurance companies in Nigeria so the best thing your brother would do is to visit their websites for more information or more still you can go to their offices located either in Ikeja, Lagos State, Nigeria or on the Island still in Lagos state, Nigeria for more information about the type of insurance he'll subscribe to.