What is the test for obtaining consent to search a locked safe?

In State v. Odom (N.D. 2006) 722 N.W.2d 370, the court ruled that it was objectively reasonable for police to search a locked safe based on the suspect's general consent to search his hotel room. (Id. at pp. 373-374.) The court based its ruling on the suspect's knowledge that the object of the search was narcotics, the fact that narcotics were likely to be hidden in the locked safe, the lack of damage or destruction to the safe (which was opened using a master key obtained from the hotel manager after the suspect denied having a key), and the suspect's failure to "withdraw or limit his consent to search the hotel room" or to indicate that his consent did not extend to the safe. (Id. at pp. 372-374.)