The following pages give guidance on how to measure grooves on club faces for width and separation, using the “Ink and Scratch” method, and depth. They concentrate solely on the Rules which apply to the grooves on iron and wood clubs manufactured prior to 1 January 2010, but, if necessary, the same procedures and equipment can be used to measure grooves on a putter face (see Rule 5f of the Equipment Rules).
For those Officials who have not carried out these measurements before, we recommend setting aside time, a day or more prior to the tournament, for groove checking if required, rather than doing it on the first day. It only takes a few minutes to measure the grooves on a club, but it is important not to be rushed. We also recommend practicemeasuring on at least six club faces – preferably more – before doing it “in the field”.
A one-page summary of the procedure for measuring the width and separation of the grooves on iron and wood clubs is attached, which, in conjunction with the specially designed results sheet, may give sufficient instruction, once the user has gained some experience in measuring grooves. An abbreviated form of the test, appropriate for clubs which comfortably meet the groove specifications, is also outlined.