delivered the opinion of the court:
The defendant, James C. Burton, was charged by complaint with unlawful use of weapons. (Ill. Rev. Stat. 1981, ch. 38, par. 24— 1(a)(4).) Prior to trial, defendant filed a motion to suppress the weapon that was seized from his person when arrested. After a hearing, that motion was granted. The State appeals (87 Ill. 2d R. 604(a)(1)), contending that the search by the metal detector was a private search, and therefore, was not subject to the exclusionary *155rule and that the frisk of defendant by the arresting police officer was valid pursuant to the exception in Terry v. Ohio (1968), 392 U.S. 1, 20 L. Ed. 2d 889, 88 S. Ct. 1868. Defendant has not filed a brief, but we will consider the merits of the State’s contentions. First Capitol Mortgage Corp. v. Talandis Construction Corp. (1976), 63 Ill. 2d 128, 345 N.E.2d 493.
The following facts were adduced at the hearing on defendant’s motion to suppress: On November 12, 1982, the defendant went to the Aragon Ballroom, which is located in the 1100 block of West Lawrence Avenue in Chicago, in order to attend the televised fight between Alexis Arguello and Aaron Pryor. At that time, he was in possession of his gun. Defendant arrived at 8:15 p.m. and purchased a ticket. He then proceeded through the outer lobby toward the door in the inner lobby. Above the door to the inner lobby was a large orange sign written in English and Spanish which warned patrons that for their safety before entering they would be checked by an electronic metal detector. The metal detector was located three feet inside the inner door.
Officer Venticinque, who was assigned that night to the area where the Aragon Ballroom is located, had stopped at that location and had informed the Aragon security personnel that he would be the tactical officer on duty that evening in the event that there were problems regarding auto theft, narcotics in the washroom and other things. Officer Venticinque happened to be standing between the warning sign and the metal detector when defendant walked in a single file through the detector at 8:15 p.m. The alarm then sounded. In response Officer Venticinque patted down defendant’s outer clothing and discovered a loaded revolver concealed on defendant’s side. The police officer then took possession of the weapon and arrested defendant on a charge of unlawful use of weapons.
It was established that the metal detectors at the ballroom were set for large quantities of metal. Defense witness Vincent DiVito testified, nonetheless, that he did not recall seeing any detectors or any signs referring to any detectors when he arrived at the ballroom at approximately 7 p.m. that same evening. He stated that he encountered three off-duty policemen who allowed him entrance without having to pass any metal detectors. However, it was established that special guests of the management were personally guided through separate entrances which were not monitored by metal detectors. DiVito further stated that he did not believe that there was a warning as to the metal detectors printed on his ticket. It was further established that metal detectors had been used for the past three years at the ballroom.
*156Defendant testified in his own behalf and denied consenting to the electronic search and also denied seeing the sign above the doorway. Although several persons were being searched in that area ahead of him, defendant indicated that he was not aware of the potential for a search.
The State also introduced two photographs of the warning signs. These photographs revealed that the warning was printed in large black letters on a fluorescent orange background. These two signs, one in Spanish and one in English, were suspended from the ceiling.
After hearing this evidence, the trial court suppressed the gun, reasoning that it was the product of the pat-down search by Officer Venticinque. The trial court based its decision solely on lack of consent, stating that the signs in the area were too ambiguous and that the ambiguity required the State to show by clear and convincing evidence that consent was freely and voluntarily given. The court concluded that the State had failed to satisfy its burden.
The State maintains that the first search was a private search, and consequently, was not subject to the exclusionary rule. The State further asserts that the second intrusion constituted a pat-down search which was justified by Terry v. Ohio (1968), 392 U.S. 1, 20 L. Ed. 2d 889, 88 S. Ct. 1868. We are in agreement with these contentions.
The burden of going forward with evidence to demonstrate legal justification shifts to the State in a suppression hearing once a defendant proves that a warrantless search has occurred and that the defendant was doing nothing unusual at the time of the search (People v. Boston (1979), 73 Ill. App. 3d 107, Ill, 391 N.E.2d 503.) However, the State is required to demonstrate the validity of a search only by a preponderance of the evidence. (See People v. Boston (1979), 73 Ill. App. 3d 107, 391 N.E.2d 503.) In rendering its decision, the trial court in the present matter adopted the reasoning of an opinion from the State of Iowa where the “clear and convincing standard” was applied. (See State v. Carter (Iowa 1978), 267 N.W.2d 385, 386.) It is evident, therefore, that the trial court in the present matter erred when it applied a standard of proof which was higher than the preponderance of the evidence standard.
Moreover, private action is not subject to the exclusionary rule of the fourth amendment because there would be no deterrent effect to punish this type of individual action. (Burdeau v. McDowell (1921), 256 U.S. 465, 475, 65 L. Ed. 1048, 1051, 41 S. Ct. 574, 576.) In addition, participation by the police in a search, in and of itself, does not automatically invoke the exclusionary rule. See People v. *157 Heflin (1978), 71 Ill. 2d 525, 539-40, 376 N.E.2d 1367.
It is true that the fourth amendment, as it applies to the States through the fourteenth amendment, requires that any search or seizure be reasonable. (Terry v. Ohio (1968), 392 U.S. 1, 8-9, 20 L. Ed. 2d 889, 898-99, 88 S. Ct. 1868, 1873.) And, to this end, the search and seizure provision of the Illinois Constitution is construed very similarly with the same provision of the Federal Constitution. (People v. Lee (1971), 48 Ill. 2d 272, 278-79, 269 N.E.2d 488.) However, probable cause for an arrest is not required in order to conduct a stop-and-frisk pursuant to Terry v. Ohio. As long as the officer has sufficient and articulable facts which create a reasonable suspicion that the person has committed or is about to commit a crime (Terry v. Ohio (1968), 392 U.S. 1, 21, 20 L. Ed. 2d 889, 905-06, 88 S. Ct. 1868, 1879-80), he may conduct a pat-down search of the outer clothing of the defendant in order to protect himself if defendant is armed (392 U.S. 1, 29, 20 L. Ed. 2d 889, 910-11, 88 S. Ct. 1868, 1884). Whether an officer believes that a subject is armed is not judged by the probable cause test; the officer need only have a reasonable belief that either his safety or the safety of others is in danger. 392 U.S. 1, 27, 20 L. Ed. 2d 889, 909, 88 S. Ct. 1868,1883.
In the present case, it was established that the Aragon Ballroom installed a metal detector in order to protect the safety of its patrons and property and also to maintain an orderly audience. The purpose of the metal detector was to detect large masses of metal, thereby deterring: the concealed possession of weapons at the ballroom. The record also establishes that the ballroom had control of the detector and bore the cost of installing and running the detector. In view of such facts, it is our opinion that the metal detector was not installed in order to obtain incriminating evidence to assist the police in catching criminals. It was primarily used to protect the patrons at the ballroom.
Moreover, it was demonstrated that Officer Venticinque was not part of the ballroom’s security plan to protect its patrons. It is true that the police officer was on duty when he made the subsequent frisk of defendant. However, it is our opinion that it was only a fortuitous circumstance that placed the police officer in the area of the metal detector when defendant triggered the alarm. Accordingly, we cannot agree with defendant’s contention at trial that the metal detector constituted State rather than private action. However, we do feel that the stop-and-frisk of defendant by Officer Venticinque constituted State action, and therefore, is subject to constitutional scrutiny.
*158 Once defendant went through the metal detector and triggered the alarm because he had a large metal mass concealed on his person, Officer Venticinque had reasonable and articulable facts from which he could presume that defendant was unlawfully carrying a concealed weapon and could be considered dangerous. Accordingly, we must conclude that the purpose of the officer’s pat-down search of defendant was not to collect evidence of a crime, but rather to protect himself and others from danger due to the possibility of a concealed deadly weapon. It was established that the scope of the pat-down search was no more intrusive than was necessary to locate a weapon. Therefore, we feel that the evidence introduced by the State clearly met the preponderance of the evidence standard in that it showed that the pat-down search by Officer Venticinque was constitutionally justified under Terry v. Ohio. Moreover, once the police officer recovered the weapon, he had probable cause to arrest defendant for unlawful use of weapons.
As indicated above, the sign in question stated: “For your safety, upon entry you will be check [sic] by an electronic metal detector.” The trial court found the wording of this sign to be ambiguous, and therefore, concluded that defendant had not voluntarily given his consent to be searched by the electronic device. In reaching its decision, the court relied upon State v. Carter, which held that certain signs posted at a particular rock concert were ambiguous. Those warnings stated that no alcoholic beverages, soft drinks, controlled substances or smoking were allowed in the auditorium and that people might be “checked” to see if they complied with these rules. The Iowa court held that there was no consent to random searches by armed, uniformed guards because the warning, which used the word “check,” gave no indication of an impending personal search. (267 N.W.2d 385, 387.) However, no metal detector was used in the Iowa case. We do not feel that the wording of the present signs, in question, was ambiguous, because there is only one way to be checked by a metal detector and that is by passing through its electronic beam.
Moreover, we believe it evident that defendant impliedly consented to this private check. Defendant did not testify that he could not turn around and leave at any time. It was established that people were lined up in single file going through the metal detector. Therefore, it is apparent that defendant was free to step out of line at any time if he did not wish to be checked. Defendant also failed to state that he was unable to read English or Spanish. The only conclusion that can be reached from these facts is that defendant *159voluntarily went through the metal detector. Since defendant’s attempt to enter the viewing area in the Aragon Ballroom manifested his willingness to submit to the check (see United States v. Doran (9th Cir. 1973), 482 F.2d 929), we must conclude that the trial court’s holding that defendant did not consent to the private search was in error.
For the foregoing reasons, the order of the circuit court of Cook County is reversed and the cause is remanded for further proceedings.
Order reversed; cause remanded.
BUCKLEY, J., concurs.