The official ball for the 2018 World Cup in Russia has received approval from EMPA, the Swiss Federal Laboratories for Materials Science and Technology, after a series of rigorous tests. (SRF, swissinfo.ch)
EMPA has been testing footballs for the world’s football governing body FIFA for 22 years, and not every ball passes the test. But although some goalkeepers had been critical of the ball’s flight characteristics, the Adidas “Telstar 18” has now got the seal of approval.
It is not only the circumference and weight of the ball that are measured precisely, according to EMPAexternal linkexternal link. Despite being crushed 250 times in a water tank, the ball may only absorb a minimal amount of liquid, must be able to hold its air and always jump off at the same height when it impacts from a height of two meters. To prove that it is a perfect sphere, the ball is also measured at no less than 4,000 points. And finally, the ball must retain its shape even if shot against a steel wall 2,000 times at 50 kilometres per hour (31 mph).
The tests were specially developed by EMPA experts in St. Gallen for official tournament footballs. When they were introduced, not all manufacturers succeeded in achieving the required properties. “Some leather balls had increased in size considerably after the procedure, or absorbed too much water,” says Martin Camenzind of the Laboratory for Biomimetic Membranes and Textiles. “Today's balls are glued or welded, because traditional seams could give way over time. Likewise, most of the traditional leather has given way to plastics, the surface of which is specifically textured, which should enable the ball to be guided more easily, especially when the field is wet.”