BOWLS
The World Bowls Board (WBB),
the international body controlling bowling throughout the world,
issued a guideline on bowling green specifications and performance
standards in July 1994. They may be summarised as follows:
5 Dimensions
Greens, square of size 36.58 to 40.23 m (40 to 44 yd.)
Ditch, of width 203 to 381 mm (8 to 15 in.) and below green 51 to
203 mm (2 to 8 in. )
Bank, max. above green 229 mm (9 in. ) angle 65 to 90 degrees
Rinks, width 5.48 to 5.79 m (18 to 19 ft.)
6 Performance
6.1 Green Speed
Test Method WBB-01
Specification: Ranges
- slow 10.0 to 12.0 s
- medium 12.1 to 14.0 s
- fast 14.1 to 16.0 s
- very fast 16.1 to 18.0 s
6.2 Draw
Test Method WBB-02
Specification: Shall be greater than 1000 mm;
Maximum difference between pairs of left and right maximum draws
shall be less than 40 %
6.3 Surface Evenness
Test Method: 300 mm and 3 m planimeters
Specification: maximum of 6 mm under 3 m straight edge undulations
between 3 and 6 mm less tha 25 % of total measured maximum of 2
mm under 300 mm straight edge
6.4 Design Levels
Test Method: Optical or laser level
Specification: deviation from the finished plane shall not be greater
than 10 mm difference in height between adjacent spot levels shall
not be greater than 6 mm
6.5 Infiltration Rate
Test method: BS 7044, Section 2.5:1991 or WBB-03
Specification: greater than 100 mm/hr at time of construction greater
than 50 mm/hr installations more than 12 months old
Testing Surfaces
The WBB operates product certification and installation compliance
schemes. Unfortunately, no Australian laboratory has been accredited
to perform this testing and clients should look overseas. For further
information contact Bowls
Australia.
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