Equipment Rules

This publication contains guidelines to help manufacturers, rules officials and other interested parties interpret the Rules relating to the design and manufacture of golf clubs and balls, as set forth in Appendices II and III of "The Rules of Golf."

Similar to the Rules, these guidelines will be continually reviewed, and modifications may be made in the future. The principles and philosophies expressed within this publication are held by both the United States Golf Association and R&A Rules Limited ("The R&A").

 

 

 

 

 

 

 

Browse the 2012-2015 Rules

SUMMARY OF
GROOVE MEASURING PROCEDURE

(The bracketed numbers refer to the corresponding paragraphs in Supplement A — “Guidance on How to Measure Grooves on Club Faces for Conformance to the 2008-2009 Rules of Golf – In The Field”)

  1. Clean club face [1]; ink the edges of five grooves in a 0.5 inch wide band [2].
  2. Check marking tool [1]; use it as described in full instructions [3] to scrape the edges of the inked grooves.
  3. Use the magnifier to measure the width of all five grooves, and record on the results sheet [4, 5, 6, 7].
  4. Measure the distance over five grooves to determine “D” [8].
  5. Measure the distance between the edges of the five grooves [8].
  6. Complete the worksheet in Supplement B of this Guide.
  7. Using quantities calculated on the worksheet, answer the questions near the bottom of the results sheet to determine whether the grooves conform [10, 11]. Manufacturers are advised to use actual widths in these calculations [12].
  8. Follow the steps on the results sheet to reach a decision on the club, repeating the measurement if necessary [11].

* * *

Note: Consult the full instructions for grooves with inconsistent spacing, or other unusual features [12, 13, 14].