I also work at Lyondell and I have worked both schedules. The DuPont schedule is ok in theory IF you can get your long changes off. The long change shift at our site is responsible for covering OT. The only way you can expect to be off on a long change is to take vacation on one side or the other. More @Wikipedia
Hover over any link to get a description of the article. Please note that search keywords are sometimes hidden within the full article and don't appear in the description or title.