ÁñÁ«ÊÓƵ

Exhibit 5.1

April 27, 2016

Board of Directors

ÁñÁ«ÊÓƵ

600 Grant Street

Pittsburgh, Pennsylvania 15219-2800

To the Board of Directors:

I am Corporate Secretary and Associate General Counsel of ÁñÁ«ÊÓƵ, a Delaware corporation (“ÁñÁ«ÊÓƵ”). I, or attorneys subject to my supervision, have served as counsel to ÁñÁ«ÊÓƵ in connection with the proposed issuance of up to 7,200,000 shares of common stock, par value $1.00 per share, of ÁñÁ«ÊÓƵ (the “Shares”) in connection with the ÁñÁ«ÊÓƵ 2016 Omnibus Incentive Compensation Plan and in the preparation and filing with the Securities and Exchange Commission of a Registration Statement on Form S-8 (“Registration Statement”) relating to such Shares.

As Corporate Secretary and Associate General Counsel of ÁñÁ«ÊÓƵ, I am familiar with ÁñÁ«ÊÓƵ’s Certificate of Incorporation and By-Laws. I am also familiar with the resolutions adopted by ÁñÁ«ÊÓƵ’s Board of Directors, authorizing the issuance of the Shares. I have examined the Registration Statement and have examined or caused to be examined such other documents, corporate records and certificates of corporate officers and public officials as I have deemed relevant or necessary to giving the opinion set forth below.

Based on the foregoing, I am of the opinion that the issuance of the Shares has been approved by all necessary corporate action and that when the Shares are sold they will be legally issued, fully paid and non-assessable.

I hereby consent to the filing of this opinion as an exhibit to the Registration Statement.