Hospitals rules on saftey?

my son is on a ventilator and he has a trach and it collects water by it and iv been helping keep the water from going into his lungs and today the nurse got all snooty and said ur not allowed to tuch it but iv been doing it for over 2 weeks and nothing has happened and non of the other nurses have said anything and i want to know if it means keeping him safe if im allowed to or not. again im just trying to find out if its for his saftey if its alright.