Sorry, how on earth do you expect someone to send you a method statement when you provided such little information detail about the task. Are you talking about the inhalation risks? Confined space risks. If compressed, assume the nitrogen is in a bottle - so pressure safety should be considered? Manual handling from a heavy bottle?? Its your job/task - you assess the risk and devise a suitable Method Statement to control the hazards and risks you have identified. Nitrogen is perfectly safe to breathe - provided it makes up about 79% of the atmosphere and the other gases include about 19.8% oxygen and other trace gases. Lazy safety management, in my view Harsh/abrupt but true.