EXHIBIT 5.1

                              December 4, 2001

Respironics, Inc.
1501 Ardmore Boulevard
Pittsburgh, PA  15221

          Re:  Registration Statement on Form S-8 for Respironics, Inc.
               1991 Non-Employee Directors' Stock Option Plan
               --------------------------------------------------------

Gentlemen:

     We have acted as counsel to Respironics, Inc., a Delaware corporation (the
"Company"), in connection with the above-captioned Registration Statement (the
"Registration Statement") relating to up to 100,000 shares of Common Stock, par
value $.01 per share, of the Company (the "Common Stock") which may be purchased
by non-employee directors pursuant to options granted under the Company's 1991
Non-Employee Directors' Stock Option Plan (the "Plan").  The Plan provides that
either authorized but unissued or treasury shares of Common Stock may be issued
and sold to non-employee directors under the Plan.  In rendering our opinion
below, we have assumed that any previously issued shares reacquired by the
Company and reissued under the Plan will have been duly authorized, validly
issued and fully paid at the time of their original issuance.

     In connection with this opinion, we have examined, among other things:

          (1)  the Certificate of Incorporation and Bylaws of the Company, as
     amended to date;

          (2)  actions taken by the Board of Directors of the Company on August
     8, 1996, authorizing the issuance of up to 100,000 shares of Common Stock
     under the Plan and reserving 100,000 shares of Common Stock for such
     purpose;

          (3)  action taken by the shareholders of the Company on November 20,
     1996 approving the issuance of an additional 100,000 shares under the
     Plan; and

          (4)  the Plan, as currently in effect.

     Based upon the foregoing and upon an examination of such other documents,
corporate proceedings, statutes, decisions and questions of law as we considered
necessary in order to enable us to furnish this opinion, and subject to the
assumptions set forth above, we are pleased to advise you that in our opinion
the 100,000 shares of Common Stock being registered and which may be issued and
sold by the Company to non-employee directors under the Plan have been duly
authorized, and upon such issuance in accordance with the provisions of the Plan
such shares will be validly issued, fully paid and nonassessable.

     In rendering the foregoing opinion, we have not examined the laws of any
jurisdiction other than the laws of the State of Delaware and federal laws of
the United States of America and the foregoing opinion is limited to such laws.

     We hereby consent to the filing of this opinion as an Exhibit to the
Registration Statement and to the use of our name in the Prospectus under the
caption "Legal Opinion."

                                 Yours truly,

                                 /s/ Reed Smith LLP

                                 REED SMITH LLP