The governing body of English cricket has been accused of discriminating against colour blind people after introducing a pink ball for the first day-night Test match on Thursday.

Colour Blind Awareness has written to the England and Wales Cricket Board (ECB) demanding it review the use of the ball which it says is very difficult to spot for people with the condition.

In a strongly worded letter seen by The Telegraph, Kathryn Albany-Ward, the founder of the organisation, warned that the ECB could be even failing colour blind cricketers under equality employment legislation because the visual impairment is seen as disability.

“In the UK there are approximately three million people with colour blindness,” the letter says, adding that that equates to possibly one colour blind cricketer in each team, 1,125 spectators at this week’s England vs West Indies Test at Edgbaston, and thousands watching the match on television around the world.

“So, it would be extremely difficult to argue that it is reasonable to use a pink ball when so many people are potentially adversely affected,” it continues. “This is an issue that urgently needs to be investigated in more detail, including adequate and detailed testing of the ball in different light conditions both by players and spectators with normal colour vision and those with different types and severities of colour blindness.”