In this case we are asked to determine whether the court of appeals properly found that the commission abused its • discretion. For the reasons that follow, we affirm the judgment of the court of appeals.

Ohio Adm.Code 4121:1-3-10(B) sets forth the relevant definitions as follows:

“(20) ‘Manually propelled mobile scaffold’ means a portable rolling scaffold equipped with casters.

“* * *

“(36) ‘Tube and coupler scaffold’ means an assembly consisting of tubing which serves as posts, bearers, braces, ties, and runner, a base supporting the posts, and special couplers which serve to connect the uprights and to join the various members.

“(37) ‘Tubular welded frame scaffold’ means a sectional panel or frame metal scaffold built up of prefabricated welded sections which consists of posts and horizontal bearers with intermediate members.”

*330The litigants agree that the scaffold from which Nobel fell qualified as a “manually propelled mobile scaffold” under Ohio Adm.Code 4121:1—3—10(B)(20). They do not dispute that the scaffold, as an assembly, was either a “tube and coupler scaffold” or a “tubular welded frame scaffold.”

Ohio Adm.Code 4121:1-3-10 reads:

“(G) Manually propelled mobile scaffolds.

“* * *

“(2) Casters shall be properly designed for strength and dimensions to support four times the maximum rated load. All casters shall be provided with a locking device to hold the scaffold in position.”

It is undisputed that the scaffold’s casters had locking devices and that one of them somehow disengaged. The commission found no (G)(2) violation because a first-time failure of a safety device cannot sustain a finding of a violation, absent employer knowledge of the defect. State ex rel. Taylor v. Indus. Comm. (1994), 70 Ohio St.3d 445, 449, 639 N.E.2d 101, 104; State ex rel. Jeep Corp. v. Indus. Comm. (1989), 42 Ohio St.3d 83, 537 N.E.2d 215; State ex rel. M.T.D. Products, Inc. v. Stebbins (1975), 43 Ohio St.2d 114, 72 O.O.2d 63, 330 N.E.2d 904. Nobel does not contest this finding.

The commission did, however, find violations of Ohio Adm.Code 4121:1-3-10(E)(12) and (F)(5), which state:

“(E) Tube and coupler scaffolds.

«* * *

“(12) The entire scaffold shall be tied to and securely braced against the building at intervals not to exceed thirty feet horizontally and twenty-six feet vertically.

“* * *

“(F) Tubular welded frame scaffolds.

“(5) To prevent movement, the scaffold shall be secured to the building or structure at intervals not to exceed thirty feet horizontally and twenty-six feet vertically.”

M & S successfully argued below that the commission’s VSSR award was an abuse of discretion because it violated the rules of requirement specificity and strict construction. Strict construction and requirement specificity are primarily rules of interpretation. The problem in this case, however, is more of application than interpretation. Individually, the specific safety requirements are clear, without the ambiguity that necessitates interpretative effort. It is the collective *331application of the three specific safety requirements that has generated the controversy before us.

In State ex rel. Harris v. Indus. Comm. (1984), 12 Ohio St.3d 152, 153, 12 OBR 223, 224, 465 N.E.2d 1286, 1288, this court held that the commission “has the discretion to interpret its own rules; however, where the application of those rules to a unique factual situation gives rise to a patently illogical result, common sense should prevail.”

Caster locks and structural tie-up have the same stated purpose — to secure the scaffold. See Ohio Adm.Code 4121:1-3-10(F)(5) (“[t]o prevent movement, the scaffold shall be secured to the building”) and (G)(2) (“[a]ll casters shall be provided with a locking device to hold the scaffold in position”). Neither caster locks nor structural tie-up is mentioned in Ohio Adm.Code 4121:1-3-10(C), which lists the general requirements for all scaffolds. We conclude that neither caster locks nor structural tie-up is necessary in all situations, whether due to a lack of hazard, the presence of an equivalent means of protection, or some other reason. Accordingly, we conclude that there are situations in which caster locks are the lone prescribed safety device.

The common purpose of caster locks and structural tie-ups and the absence of a requirement for secondary protection within the individual specific safety requirements suggest that the code’s authors viewed the two methods as providing equivalent protection. We conclude that it is illogical to require an employer to provide duplicate protection in the absence of a duplicate-protection requirement. For the reasons stated above, we affirm the judgment of the court of appeals.

Judgment affirmed.

dissent and would reverse the judgment of the court of appeals and return this cause to the Industrial Commission for additional findings.