This was taken from
http://www.nachi.org/aboutexam.htm I heard that NACHI's Online Inspector Examination is too easy. Is this true?
No. The exam is difficult for some and easy for others. Only about 1/2 the people who take the exam for the first time pass. The average grade is failing. You need a score of 75 to pass. NACHI gathers national statistics about each question on the exam. These statistics are automatically updated every time someone takes the exam. Statistics concerning level of difficulty are displayed for each question as you take the exam. Some of the national statistics about the exam, including pass/fail rates, are available on our web site. Critics must recognize that this exam is NACHI's entrance exam. Passing the exam is required to join NACHI. Other associations have no entrance requirements. Pets and blind men can and have joined other national associations.
I heard that NACHI's Online Inspector Examination is too difficult. Is this true?
No. The exam is difficult for some and easy for others. A general understanding of residential construction and components is helpful. Most exam takers who have a background in construction are able to pass on the first attempt even though they have no inspection experience. Remember, if you fail we can use your exam results to help determine what you need to study. NACHI gathers national statistics about each question on the exam. These statistics are automatically updated every time someone takes the exam. Statistics concerning level of difficulty are displayed for each question as you take the exam. Some of the national statistics about the exam, including pass/fail rates, are available on our web site.
I understand that the exam contains too many questions about wiring and electricity. Why?
It is true that the exam contains extra questions about wiring and electricity. Although wiring and electricity is only a small part of a home inspection, it is one of the more important parts. This is because electrical problems, unlike plumbing for example, can destroy property and kill people.
Also, passing this exam does not get you a membership:
http://www.nachi.org/membership.htm