N.J. Stat. § 4:12-41.2
No person, nor any employee of such person, shall use in the determination of the butter fat content of milk or cream any test glassware, or centrifuges except such as conform to the requirements of the United States Bureau of Standards and which have been inspected, tested and approved by the director. For each inspection the director shall have the right to make a reasonable charge, not in excess of five cents ($0.05) per item. Every piece of test glassware inspected by the director and found to be correct shall be marked by the director with the letters "S.G.N.J." (Standard Glassware New Jersey) and promptly returned to the owner or disposed of as directed, and the use of such glassware not bearing the letters "S.G.N.J." shall constitute a violation of this act. No method other than the "Babcock" test or the "Gerber" test shall be used in determining the butter fat percentage of milk or cream until such test has been approved by the director. Every installation of laboratory equipment to be used in determining the butter fat content of milk or cream shall be inspected and approved by the director. The use of an unapproved installation is a violation of this act.
N.J.S. § 4:12-41.2