It's very hard to break a broody hen so don't confuse a hen sitting on the nest to lay her egg a sign of broodiness. Some of them get a bit irritated when they are bothered - like they have to concentrate or something to get that egg laid...lol
Most often a broody will growl if you come close to her and the nest. She might allow other hens to come and lay eggs but WILL NOT be pushed off the nest easily, and she will get off to eat and poop but will get right back on the eggs. The best thing to do when you suspect you have a broody hen is to move her and the eggs to a private spot where she won't be bothered by others, and if she continues to sit on the nest for a few days then I would swap the eggs she was sitting on for a clutch of 12-16 fresh ones. (That way there won't be a staggered hatch and risk of the hen getting off the later eggs that aren't hatched to look after the few early ones that did hatch.
RIRs are not a breed known to go broody (but there are exceptions) - The best way of hatching chicks is to get yourself an incubator. You can set a clutch any time without taking a chance waiting for a hen to go broody.
