The one question presented on this appeal is whether the court erred in granting defendant’s motion for a directed verdict. Plaintiff contends the court did err in granting the motion because the evidence established a prima facie case of defendant’s actionable negligence.

No inference of negligence on the part of the store owner arises from the mere fact that a customer falls on the floor of his store since the doctrine of res ipsa loquitur is inapplicable in such circumstances. Hinson v. Cato’s, Inc., 271 N.C. 738, 157 S.E. 2d 537. (1967); Dawson v. Light Co., 265 N.C. 691, 144 S.E. 2d 831 (1965). Store owners are not the insurers of the safety of customers on their premises. Long v. Food Stores, 262 N.C. 57, 136 S.E. 2d 275 (1964); Copeland v. Phthisic, 245 N.C. 580, 96 S.E. 2d 697 (1957).

The proprietor does owe to his customers the duty to exercise ordinary care to maintain in a reasonably safe condition those portions of his premises which he may expect they *216 will use during business hours, and to give warning of hidden peril or unsafe conditions insofar as these can be ascertained by reasonable inspection and supervision. Dawson v. Light Co., supra; Lee v. Green & Co., 236 N.C. 83, 72 S.E. 2d 33 (1952). If the unsafe condition is created by third parties or an independent agency, a showing must be made that it had existed for such length of time that the store proprietor knew or by the exercise of reasonable care should have known of its existence in time to have removed the danger or given warning of its presence. Dawson v. Light Co., supra; Hughes v. Enterprises, 245 N.C. 131, 95 S.E. 2d 577 (1956).

“The proprietor of a business establishment is not required to take extraordinary precautions for the safety of his invitees, the measure of his duty in this respect being to exercise reasonable or ordinary care. 65 C.J.S. Negligence § 63 (121), p. 888.” Gaskill v. A. and P. Tea Co., 6 N.C. App. 690, 694, 171 S.E. 2d 95, 97 (1969).

Considering the evidence in this case in the light most favorable to the plaintiff and applying the foregoing principles of law, we are of the opinion that the evidence is not sufficient to support a findng that plaintiff’s injuries were proximately caused by defendant’s negligence. While the evidence does tend to show, as plaintiff contends, that defendant knew that the terrazzo floor was slippery when wet, and that on the day plaintiff fell the defendant knew that water accumulated on the floor from time to time, the evidence is not sufficient to raise the inference that the defendant did not take reasonable precautions to protect its patrons from any dangerous condition created by the accumulation of water on the floor. Indeed plaintiff’s own evidence discloses that the defendant mopped, cleaned, and dried the floor periodically throughout the morning, and the area where plaintiff fell had been cleaned and dried just ten minutes prior to the accident complained of.

The case of Powell v. Deifells, Inc., 251 N.C. 596, 112 S.E. 2d 56 (1960), cited and relied upon by plaintiff, is distinguishable by the fact that in that case defendant took no precaution at all to protect its customers from the dangerous condition created by a wet, slippery floor.

Affirmed.