Break in marks are in the Ops rules not the aircraft cert rules. See extract from EU-OPS below. Also note the wording "if designated areas..." etc. This means you do not have to have break in markings but if you do they must conform to 1.800.
OPS 1.800
Marking of break-in points
An operator shall ensure that, if designated areas of the fuselage suitable for break-in by rescue crews in emergency are marked on an aeroplane, such areas shall be marked as shown below. The colour of the markings shall be red or yellow, and if necessary they shall be outlined in white to contrast with the background. If the corner markings are more than 2 metres apart, intermediate lines 9 cm x 3 cm shall be inserted so that there is no more than 2 metres between adjacent marks.