SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549
                                   ----------
                                  SCHEDULE 13G
                                 (RULE 13D-102)

             INFORMATION STATEMENT PURSUANT TO RULES 13D-1 AND 13D-2
                    UNDER THE SECURITIES EXCHANGE ACT OF 1934
                               (AMENDMENT NO. 21)

                         MINE SAFETY APPLIANCES COMPANY
                         ------------------------------
                                (Name of Issuer)

                                  Common Stock
                                  ------------
                         (Title of Class of Securities)

                                    602720104
                                    ---------
                                 (CUSIP Number)

                                December 31, 2001
                                -----------------
             (Date of Event Which Requires Filing of this Statement)

Check the appropriate box to designate the rule pursuant to which this Schedule
is filed:

[X] Rule 13d-1(b)
[ ] Rule 13d-1(c)
[ ] Rule 13d-1(d)

CUSIP No. 602720104                                            Page 1 of 5 Pages

   1)  Names of Reporting Persons
       IRS Identification No. Of Above Persons

            The PNC Financial Services Group, Inc. (formerly, PNC Bank Corp.)
            25-1435979

   2)  Check the Appropriate Box if a Member of a Group (See Instructions)
       a) [ ]
       b) [ ]

   3)  SEC USE ONLY

   4)  Citizenship or Place of Organization    Pennsylvania

   Number of Shares        5)  Sole Voting Power                       1,120,382

   Beneficially Owned      6)  Shared Voting Power                           -0-

   By Each Reporting       7)  Sole Dispositive Power                     15,432

   Person With             8)  Shared Dispositive Power                1,415,673

   9)  Aggregate Amount Beneficially Owned by Each Reporting Person   2,535,755*
                                       *See the response to Item 4.
   10) Check if the Aggregate Amount in Row (9) Excludes Certain Shares
       See Instructions                                                      [ ]

   11) Percent of Class Represented by Amount in Row (9)                  18.80*
                                       *See the response to Item 4.
   12) Type of Reporting Person  (See Instructions)                           HC


                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549
                                   ----------
                                  SCHEDULE 13G
                                 (RULE 13D-102)

             INFORMATION STATEMENT PURSUANT TO RULES 13D-1 AND 13D-2
                    UNDER THE SECURITIES EXCHANGE ACT OF 1934
                               (AMENDMENT NO. 21)

                         MINE SAFETY APPLIANCES COMPANY
                         ------------------------------
                                (Name of Issuer)

                                  Common Stock
                                  ------------
                         (Title of Class of Securities)

                                    602720104
                                    ---------
                                 (CUSIP Number)

                                December 31, 2001
                                -----------------
             (Date of Event Which Requires Filing of this Statement)

Check the appropriate box to designate the rule pursuant to which this Schedule
is filed:

[X] Rule 13d-1(b)
[ ] Rule 13d-1(c)
[ ] Rule 13d-1(d)

CUSIP No. 602720104                                            Page 2 of 5 Pages

   1)  Names of Reporting Persons
       IRS Identification No. Of Above Persons

            PNC Bancorp, Inc.  51-0326854

   2)  Check the Appropriate Box if a Member of a Group (See Instructions)
       a) [ ]
       b) [ ]

   3)  SEC USE ONLY

   4)  Citizenship or Place of Organization    Delaware

   Number of Shares        5)  Sole Voting Power                       1,120,382

   Beneficially Owned      6)  Shared Voting Power                           -0-

   By Each Reporting       7)  Sole Dispositive Power                     15,432

   Person With             8)  Shared Dispositive Power                1,415,673

   9)  Aggregate Amount Beneficially Owned by Each Reporting Person   2,535,755*
                                       *See the response to Item 4.
   10) Check if the Aggregate Amount in Row (9) Excludes Certain Shares
       See Instructions                                                      [ ]

   11) Percent of Class Represented by Amount in Row (9)                  18.80*
                                       *See the response to Item 4.
   12) Type of Reporting Person  (See Instructions)                           HC


                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549
                                   ----------
                                  SCHEDULE 13G
                                 (RULE 13D-102)

             INFORMATION STATEMENT PURSUANT TO RULES 13D-1 AND 13D-2
                    UNDER THE SECURITIES EXCHANGE ACT OF 1934
                               (AMENDMENT NO. 21)

                         MINE SAFETY APPLIANCES COMPANY
                         ------------------------------
                                (Name of Issuer)

                                  Common Stock
                                  ------------
                         (Title of Class of Securities)

                                    602720104
                                    ---------
                                 (CUSIP Number)

                                December 31, 2001
                                -----------------
             (Date of Event Which Requires Filing of this Statement)

Check the appropriate box to designate the rule pursuant to which this Schedule
is filed:

[X] Rule 13d-1(b)
[ ] Rule 13d-1(c)
[ ] Rule 13d-1(d)

CUSIP No. 602720104                                            Page 3 of 5 Pages

   1)  Names of Reporting Persons
       IRS Identification No. Of Above Persons

            PNC Bank, National Association  22-1146430

   2)  Check the Appropriate Box if a Member of a Group (See Instructions)
       a) [ ]
       b) [ ]

   3)  SEC USE ONLY

   4)  Citizenship or Place of Organization    United States

   Number of Shares        5)  Sole Voting Power                       1,120,382

   Beneficially Owned      6)  Shared Voting Power                           -0-

   By Each Reporting       7)  Sole Dispositive Power                     15,432

   Person With             8)  Shared Dispositive Power                1,415,673

   9)  Aggregate Amount Beneficially Owned by Each Reporting Person   2,535,755*
                                       *See the response to Item 4.
   10) Check if the Aggregate Amount in Row (9) Excludes Certain Shares
       See Instructions                                                      [ ]

   11) Percent of Class Represented by Amount in Row (9)                  18.80*
                                       *See the response to Item 4.
   12)  Type of Reporting Person  (See Instructions)                          BK


                                                               Page 4 of 5 Pages

ITEM 4 - OWNERSHIP:

The following information is as of December 31, 2001:

(a)  Amount Beneficially Owned:                                2,535,755 shares*

(b)  Percent of Class:                                                    18.80*

(c)  Number of shares to which such person has:
         (i)  sole power to vote or to direct the vote                 1,120,382
        (ii)  shared power to vote or to direct the vote                     -0-
       (iii)  sole power to dispose or to direct the disposition of       15,432
        (iv)  shared power to dispose or to direct the disposition of  1,415,673

       *Of the total shares of Common Stock reported herein, 1,072,500 shares
       are held in a pension plan trust account opened on June 13, 2000 under
       the plan name of "Non-Contributory Pension Plan for Employees of Mine
       Safety Appliances Company." The account was established under that
       certain Trust Agreement dated April 1, 1992 by and between Mine Safety
       Appliances Company and Pittsburgh National Bank (now, PNC Bank, National
       Association) for which PNC Bank, National Association serves as Directed
       Trustee.

       *On June 4,1996, the Mine Safety Appliances Company Stock Compensation
       Trust (the "Trust"), of which PNC Bank, National Association, acts as
       Trustee, purchased 600,000 shares of common stock, no par value, of Mine
       Safety Appliances Company (the "Company"). The purchase price for such
       common stock was paid for by a loan from the Company to the Trustee as
       evidenced by a promissory note. The Trust was established and the
       Company's common stock so purchased to provide assurance of the
       availability of the shares of the Company's common stock necessary to
       satisfy certain obligations of the Company and its subsidiaries under
       certain designated non-qualified employee plans, in accordance with a
       Trust Agreement effective as of June 1, 1996. On May 25, 2000, the
       Company declared a 3-for-1 stock split thereby increasing the number of
       total shares in the Trust from 600,000 to 1,800,000. Pursuant to this
       amendment to Schedule 13G, PNC Bank, National Association, as Trustee of
       the Trust, reports that it has no voting power, but may have shared
       dispositive power, with respect to the 1,415,373 shares held in the Trust
       as of December 31, 2000. The filing of this amendment does not
       constitute, and should not be construed as, an admission that either PNC
       Bank, National Association, as Trustee of the Trust, or the Trust
       beneficially owns such securities. In connection therewith, the Trustee
       and the Trust disclaim beneficial ownership of such securities.


ITEM 7 - IDENTIFICATION AND CLASSIFICATION OF THE SUBSIDIARY WHICH ACQUIRED THE
         SECURITY BEING REPORTED ON BY THE PARENT HOLDING COMPANY:

Included are the following subsidiaries of The PNC Financial Services Group,
Inc. (formerly, PNC Bank Corp.) - HC:

PNC Bancorp, Inc. - HC (wholly owned subsidiary of PNC Bank Corp.)

PNC Bank, National Association - BK (wholly owned subsidiary of PNC Bancorp,
Inc.)


                                                               Page 5 of 5 Pages



ITEM 10 - CERTIFICATION:

         By signing below I certify that, to the best of my knowledge and
belief, the securities referred to above were acquired and held in the ordinary
course of business and were not acquired and are not held for the purpose of or
with the effect of changing or influencing the control of the issuer of the
securities and were not acquired and are not held in connection with or as a
participant in any transaction having that purpose or effect.


                                    SIGNATURE

         After reasonable inquiry and to the best of my knowledge and belief, I
certify that the information set forth in this statement is true, complete and
correct.


February 12, 2002
-----------------------------------------------------------------------
Date


By: /s/ Robert L. Haunschild
-----------------------------------------------------------------------
Signature - The PNC Financial Services Group, Inc.
Robert L. Haunschild, Senior Vice President and Chief Financial Officer
-----------------------------------------------------------------------
Name & Title


February 12, 2002
-----------------------------------------------------------------------
Date


By: /s/ James B. Yahner
-----------------------------------------------------------------------
Signature - PNC Bancorp, Inc.
James B. Yahner, Vice President
-------------------------------
Name & Title


February 12, 2002
-----------------------------------------------------------------------
Date


By: /s/ Thomas R. Moore
-----------------------------------------------------------------------
Signature - PNC Bank, National Association
Thomas R. Moore, Secretary
--------------------------
Name & Title


                     AN AGREEMENT TO FILE A JOINT STATEMENT
             WAS PREVIOUSLY FILED AS EXHIBIT A TO AMENDMENT NO. 11.