KK,
There are many threads within this database with more information about your question than you can shake a stick at. You can find them pretty easy by using the 'Search' function here.
Also, if you go to the main website, then to 'certifications', then 'Certified Welding Inspector', then 'CWI Program Package', down toward the bottom will be a section on 'self study materials'. All the recommended materials are good to have even after you test. Some are references that will be handed out the week of the seminar and exam. It is still beneficial, though not mandatory nor absolutely necessary, to purchase them ahead of time and study them before ever reaching the seminar. You can always sell or hand out the extras to fellow employees or others interested in improving their welding knowledge.
The main item to study is your D1.1. My second choice would be the WIT book. From there, there are many opinions. None are wrong. It all depends upon how serious you are and how deep your pockets are. The Certification Handbook is another good one. Several people here really like it for pre-exam study. The WIT book will be given to you and gone through at the seminar, but, as you will get a closed book exam of a couple hundred questions from it, it does not hurt to know it well.
The area I directed you to for the references will also show you some free downloads that will explain all the requirements and qualifications to become a CWI. QC1 would be very beneficial to go through as would B5.1.
Hope this is of some help.
Have a Great Day, Brent
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