Hoop Specification and Approvals
To provide security for clubs considering purchasing new types of hoops, the CA initiated an Approval Scheme in December 2000. Approved hoops are recognised for use in CA Tournaments and Championships, but the use of Approved hoops is not a requirement in such events.
Standard Approval may be given to hoops of unstressed upright separation 311/16 inches to 313/16 inches, and both Championship and Standard Approvals to those with separation in the range 311/16 inches to 33/4 inches. The Championship range provides for a 1/16 inch clearance on all Championship Approved balls and the different upper limit of the Standard range accommodates a 1/8 inch clearance. By stressing the hoops in the ground it is expected that most designs will produce both 1/16 inch and 1/8 inch settings at ball half-height; the rules for Approval also aim to cover fixed width hoops such as may be more suitable for use with artificial surfaces.
The requirements in Section 2(c) were revised in 2009 to recognise widespread use of hoops of greater upright diameter than 5/8 inch diameter, problems with the production of cast iron hoops with 5/8 inch, and a strong interest in the upper reaches of the game in providing hoops of significant challenge. The revision of the Laws in 2008 to increase the upward tolerance on the 5/8 inch dimension by 1/8 inch was therefore interpreted in Approval regulations 2(c) and 2(e) to permit the use of 3/4 inch diameter uprights and crown.
Currently Approved Hoops are as follows:
- Omega Adjustable Hoop (Steel; Standard and Championship Approval, December 2000)
- Jaques Championship Hoop (Cast Iron; Standard and Championship Approval, July 2005)
- Hopewell Championship Hoop (Standard and Championship Approval, April 2010)
- GW Championship Hoop (Steel; Standard and Championship Approval, December 2011)
- Atkins Quadway adjustable stainless steel hoop (approved from March 2013)
- Aldridge Championship Hoop (Standard and Championship Approval October 2017)
- Holdfast Croquet Hoop (Standard and Championship Approval August 2019)
- SACA Competition Hoop (Standard and Championship Approval January 2020)
See the CA online shop for hoop details.
The design of a hoop system for use with artificial surfaces by R. H. Rawden of the Bury St Edmunds Club was Approved in 2003.
Makers intending to produce Approved hoops are invited to make contact with the Chairman of the CA's Equipment Committee.
Manufacturers seeking Approval are required to submit one (non-returnable) fully finished hoop for testing, to arrange a Field Test at an agreed venue and for an agreed period, and to provide written assurance that the manufacturing processes are adequately reproducible. The Equipment Committee is responsible for preparing a report of performance in relation to the stated criteria and will provide a checklist of items for the Field Test. The report will include a general description of the hoop system and indicate whether the hoop is suitable for fixed or adjustable setting. Approvals will be announced in an appropriate manner by the CA. A hoop system may be accorded Approval in either or both of the Standard/Championship categories. The report will be made available to the maker and for an Approved hoop it may be published by the CA.
2. CA Standard and CA Championship Approval of Hoops
Imperial measurements are definitive; metric equivalents are given for convenience. The criteria apply to hoops of fixed setting and to hoops whose setting may be adjusted by stress through the anchorages or otherwise.
Notes of explanation are enclosed in square brackets. The specifications for Approval are derived from the requirements for clearances of 1/8 inch ('handicap setting') or 1/16 inch ('advanced setting') with any ball meeting the internationally recognised Championship Approval standard - i.e. diameter 319/32 - 321/32 inches.
- A hoop comprises two vertical uprights joined at the top by a horizontal crown and must be provided with a means of anchorage at the base of the uprights.
- The uprights and crown should be straight and the anchorage system must not hinder free passage of the ball.
- The uprights and crown must be constructed of solid metal of adequate hardness and the hoop must be rigid.
- The hoop must be capable of a setting in which the top of the crown is between 11.5 and 12.5 inches (292 and 317 mm) from the ground.
(c) Upright Diameter
- The diameter of each upright should lie between 19/32 and 3/4 inches (15.1 and 19.1 mm); minor deviations at the top and bottom are permitted. Hoops with uprights formed from well-made 3/4 inch bar will be deemed to fulfil the requirements for Approval.
- Three measurements are to be made for each upright: high, low and mid length: all diameters must lie within the allowed range. Here and subsequently, high = approx. 13/4 inches from underside of crown; low = approx. 13/4 inches above base of upright.
- The high and low points avoid minor deviations at the top and bottom of the uprights and approximate respectively to a ball radius from the underside of the crown or the ground (13/4 inches = ideal ball radius minus 1/16 inch).
(d) Uprights Parallel
- The inner surfaces of the uprights must be approximately parallel and of separation between 311/16 and 313/16 inches (93.7 and 96.8 mm) for Standard Approval or between 311/16 and 33/4 inches (93.7 and 95.25 mm) for Championship Approval. For a set of hoops the separations must not differ by more than 1/16 inch (1.6 mm).
- Three measurements of the separation between the inner surfaces of the uprights of an unstressed hoop are to be made at high, low and mid length: all three measurements must be within the allowed range and the difference between the largest and smallest measurement shall not exceed 1/32 inch; for a set of hoops the difference between the largest and smallest of the 18 measurements should not exceed 1/16 inch.
The ranges are derived as follows.
- Standard Approval:
319/32 (min. ball) + 1/8 (handicap setting) - 1/32 (hoop tolerance) = 311/16 inches
321/32 (max. ball) + 1/8 (handicap setting) + 1/32 (hoop tolerance) = 313/16 inches
- Championship Approval:
321/32 (max. ball) + 1/32 (min. clearance) = 311/16 inches
321/32 (max. ball) + 1/16 (advanced setting) + 1/32 (hoop tolerance) = 33/4 inches]
The uprights between the high and low positions will be tested for coplanarity: when one upright is in contact with a plane surface, no point of the relevant length of the other upright may depart from the plane by more than 1/16 inch.
- The crown must be straight, at right angles to the uprights, and have a diameter between 19/32 and 3/4 inch (15.1 and 19.1 mm).
- Any logo must comply with these limits.
(f) Field Test
- The hoop must be capable of being set firmly in suitable ground.
- Evidence of satisfactory performance in setting, durability, and play with Championship Approved balls must be available.
- A check list will be prepared to ensure that the Field Test has appropriate scope.