The jump jockey received his punishment from the local stewards after they found he had taken the wrong course in the Sedgefielders Racing App Durham National Handicap Chase on Sunday.
Riding Red Giant for Jennie Candlish, Quinlan was in front heading to the second-last fence on the final circuit in the three-mile-five-furlong contest.
But that fence had been omitted on the second of three circuits because of a nasty incident at the seventh which left jockey Page Fuller injured after her horse Fact Of The Matter fell, badly hampering Easy Street.
The obstacle was reintroduced, but Quinlan pulled his mount round it again and then pulled up after the other jockeys successfully negotiated it.
“The first concern, of course, is safety. An obstacle will not be reintroduced unless it can be jumped safely,” said a BHA spokesman.
“If an assessment is made that an obstacle can be reintroduced without putting anybody – including horse, rider, medical and veterinary staff – at any extra risk, then it will be brought back into the race, in order to be fair to participants and the betting public by retaining the original character and challenge of the race.
“The instructions to jockeys are very clear and intended to take all the decision-making out of it for them. Basically – if a fence has direction markers in it, don’t jump it. If it doesn’t have direction markers in it, then jump it.
“All riders are reminded of this at the National Hunt Jockeys seminars and at the courses that conditional jockeys attend at the racing schools.
“It happens from time to time that fences are reintroduced, and we have never had an issue before – and neither was there any uncertainty among the other riders in this race.”