An entrenched rule of constitutional law is that the Fourth Amendment bars unreasonable searches and seizures. (Maryland v. Buie (1990) 494 U.S. 325, 331 (Buie).) When determining reasonableness, a balance must be struck between the intrusion on an individual's Fourth Amendment rights and "its promotion of legitimate governmental interests." (Ibid.) Searches of a house, for instance, are generally not reasonable without a warrant issued on probable cause. (Ibid.) Nevertheless, because of the need to balance these competing interests, there are exceptions where neither a warrant nor probable cause is required. (Ibid.) One such exception is the protective sweep. A protective sweep is "a quick, limited premises search incident to a lawful arrest at a residence." (4 Witkin & Epstein, Cal. Criminal Law (4th ed. 2012) Illegal Evidence, 346, p. 1210.) The rationale for a protective sweep is to protect officers from an immediate risk of harm at the site of an arrest. (Buie, supra, 494 U.S. at p. 333 analogizing the safety concerns of a protective sweep to those associated with a "frisk" as established in Terry v. Ohio (1968) 392 U.S. 1, or a search of a car for weapons in Michigan v. Long (1983) 463 U.S. 1032.) The protective sweep is not limited to circumstances immediately following an arrest. It may also occur in conjunction with detention or a valid probation search. (Werner, supra, 207 Cal.App.4th at p. 1206; see also People v. Ledesma (2003) 106 Cal.App.4th 857, 864 protective sweep may precede a probation search.) "An in-home arrest puts the officer at the disadvantage of being on his adversary's 'turf.' An ambush in a confined setting of unknown configuration is more to be feared than it is in open, more familiar surroundings." (Buie, supra, at p. 333.) However, the interest of protecting individual privacy restricts the scope of the sweep. The protective sweep exception does not permit a full search of the premises. It is limited to a "cursory inspection of those spaces where a person may be found." (Id. at p. 335.) A protective sweep "'does not require probable cause to believe there is someone posing a danger to the officers in the area to be swept.'" (Werner, supra, 207 Cal.App.4th at p. 1205.) Rather, it can be justified when there is merely "'a reasonable suspicion that the area to be swept harbors a dangerous person.'" (Ibid.) However, it cannot be based on an "'"unparticularized suspicion or 'hunch.'"'" (Celis, supra, 33 Cal.4th at p. 678.) The test, as established in Buie, "requires a reasonable suspicion both that someone is in the premises and that that person is dangerous." (Werner, supra, at p. 1206.) The existence of a reasonable suspicion is determined by the totality of the circumstances and whether officers had "'"a particularized and objective basis"' for his or her suspicion." (Ibid.) It must be shown that "articulable facts," known to the officers before the protective sweep began and considered with the rational inferences drawn from those facts, existed that "would warrant a reasonably prudent officer to entertain a reasonable suspicion that the area to be swept harbors a person posing a danger to officer safety." (Celis, supra, at pp. 679-680.)