*1103DISSENTING OPINION BY
Senior Judge FRIEDMAN.Because I disagree with the majority’s conclusion that the arbitrator’s award was not rationally derived from the Collective Bargaining Agreement (CBA) between the School District of Philadelphia (District) and the Philadelphia Federation of Teachers, Local 3 (PFT), I respectfully dissent. Accordingly, I would affirm the order of the Court of Common Pleas of Philadelphia County (trial court).
Article IX of the CBA addresses “Employment Security” for all District employees. Article IX, Section B(l) of the CBA provides:
1. The parties agree that all employees who were regularly appointed to a full-time and/or part-time position during the 1979-1980 school year (i.e. September 1, 1979 to June 30, 1980) shall continue to be employed in their positions and be guaranteed full and complete job security during the term of this Agreement, except that in each job classification, [all other ] employees may be laid off only in proportion to the projected decline in pupil enrollment as of the allotment date for each year of this Agreement, such layoff to be effective in any year only after giving notice to affected employees and to the Federation on or before June 30 of that year.
(R.R. 68a (emphasis added).)
The arbitrator determined that this provision of the CBA covers all District employees and provides employees appointed during the 1979-1980 school year with “full and complete” job security. Further, the provision subjects employees who were not appointed during the 1979-1980 school year to layoffs when enrollment declines.
The arbitrator noted the patent ambiguity in the CBA by stating that: “the language of Article IX[, Section] B, when considered in its totality, is not a model of clarity.” (Arb. Award at 19.) The arbitrator determined that “pursuant to Article IX, Section B(l)[,] job secured Teachers do indeed have ‘full and complete job security.’ Whatever the application and use of the second part of Article IX[, Section] B(l) might be for non-job-secured Teachers, that part of Article IX[, Section] B(l) is not applicable to job secured Teachers like the Grievants.” (Id. at 21-22.) This is a rational interpretation of the CBA.
The majority, however, interprets the CBA differently. The majority finds that Article IX, Section B(l) of the CBA “establishes a general rule of ‘full and complete job security’ for all employees who were regularly appointed from September 1, 1979 to June 30, 1980,” and “sets forth an exception to this rule, whereby generally job-secured teachers ‘may be laid off only in proportion to the projected decline in pupil enrollment....’” (Maj. Op. at 1102.)
Had the arbitrator made the findings of fact and conclusions of law that the majority believes he should have made, I would have been constrained by our deferential standard of review to affirm that decision. But the arbitrator did not interpret the CBA as the majority has. In essence, the majority believes that its interpretation is more rational than the arbitrator’s, but that is irrelevant.
In Danville Area School District v. Danville Area Education Association, PSEA/NEA, 562 Pa. 238, 754 A.2d 1255, 1260 (2000) (citation omitted), the Pennsylvania Supreme Court made it abundantly clear that “an arbitrator’s award may draw its essence from the [CBA] if the arbitrator’s ‘interpretation can in any rational way be derived from the agreement, viewed in light of its language, its context, *1104and any other indicia of the parties’ intention.’ ” A review for reasonableness is not appropriate because “it would invite a reviewing court to substitute its own interpretation of the contract language for that of the arbitrator.” Westmoreland Intermediate Unit # 7 v. Westmoreland Intermediate Unit # 7 Classroom Assistants Educational Support Personnel Association, PSEA/NEA, 595 Pa. 648, 939 A.2d 855, 863 (2007). That is exactly what the majority here has done: substituted its own interpretation of the CBA for the arbitrator’s, failed to afford an appropriate level of deference to the arbitrator’s award, and overstepped the limitations of the standard of review.
In light of the two rational interpretations of Article IX, Section B(l) of the CBA, I would find that the arbitrator’s determination was derived from the essence of the CBA. See Hutchison v. Sunbeam Coal Corporation, 513 Pa. 192, 519 A.2d 385, 390 (1986) (noting that a contract is ambiguous if its terms are reasonably or fairly susceptible to “different constructions and capable of being understood in more than one sense”). Having determined that Article IX, Section B(l) of the CBA includes an ambiguity, the arbitrator was permitted to ascertain the parties’ intent for the language of the provision by examining the parties’ past practices. See Danville, 754 A.2d at 1260 (“[Wjhere there is ambiguity, an arbitrator may attempt to discern the intent of the parties, and thus, resolve a dispute over contract interpretation, by considering the actions of the parties as evidence of their interpretation of the terms of a [CBA].”). In doing so, the arbitrator concluded that all employees hired during the 1979-1980 school year that had been laid off previously were subsequently reinstated because the layoff violated the explicit guarantee of “full and complete” job security. {See Arb. Award at 19-20.)
For these reasons, I would affirm the trial court’s order.