Based on the Department’s analysis of a representative sample of tiering results, some facilities will see a change in their tiers. Some facilities that were previously not covered under CFATS will find themselves covered, and some currently-covered facilities may no longer be considered high-risk. Some of these tier changes are a result of changes to the tiering methodology, while others are the result of changes facilities have made to their businesses, such as adding new chemicals, removing chemicals of interest, or modifying storage methods.
Again, the methodology of your work should be in strong accordance with the initial thesis and the main aim of your research. Visit the university library - the librarians might be eager to provide you with a good textbook as well as with a recommendation on how to start a cover letter . Thus, a lot of books can teach you research philosophy, so that you will be able to choose methods on your own. Moreover, it is convenient to look for someone else's thesis methodology example in the library. Remember, only deep theoretical knowledge can help you to reinforce your dissertation with firm methodological underpinnings.