EXHIBIT 99.1
 
                             LETTER OF TRANSMITTAL
 
                                   TO TENDER
              UNREGISTERED 11% SENIOR SUBORDINATED NOTES DUE 2008
                                       OF
                     MEDIQ/PRN LIFE SUPPORT SERVICES, INC.
 
   PURSUANT TO THE EXCHANGE OFFER AND PROSPECTUS DATED                 , 1998
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    THE EXCHANGE OFFER AND WITHDRAWAL RIGHTS WILL EXPIRE AT 5:00 P.M., NEW YORK
   CITY TIME, ON               , 1998 (THE "EXPIRATION DATE"), UNLESS THE
   EXCHANGE OFFER IS EXTENDED BY THE COMPANY.
 
- --------------------------------------------------------------------------------
 
                 THE EXCHANGE AGENT FOR THE EXCHANGE OFFER IS:
 
                          UNITED STATES TRUST COMPANY
                                  OF NEW YORK
 

                                                          
   BY OVERNIGHT COURIER AND         BY HAND UP TO 4:30 PM:        BY REGISTERED OR CERTIFIED
   BY HAND AFTER 4:30 PM ON                                                 MAIL:
  THE EXPIRATION DATE ONLY:
 
 United States Trust Company     United States Trust Company     United States Trust Company
         of New York                     of New York                     of New York
   770 Broadway, 13th Floor              111 Broadway                    P.O. Box 844
   New York, New York 10003              Lower Level                    Cooper Station
Attn: Corporate Trust Services     New York, New York 10006     New York, New York 10276-0844
                                Attn: Corporate Trust Services  Attn: Corporate Trust Services
                                   Telephone (800) 548-6565
                                  Fascimile: (212) 780-0592
                                        (212) 420-6211

 
(Originals of all documents sent by facsimile should be sent promptly by
registered or certified mail, hand                         delivery, or
                          overnight delivery service.)
 
  DELIVERY OF THIS LETTER OF TRANSMITTAL TO AN ADDRESS OR TRANSMISSION OF
      INSTRUCTIONS VIA FACSIMILE OTHER THAN AS SET FORTH ABOVE WILL NOT
                          CONSTITUTE A VALID DELIVERY.
 
IF YOU WISH TO EXCHANGE UNREGISTERED 11% SENIOR SUBORDINATED NOTES DUE 2008
  FOR AN EQUAL AGGREGATE PRINCIPAL AMOUNT OF REGISTERED 11% SENIOR
    SUBORDINATED NOTES DUE 2008 PURSUANT TO THE EXCHANGE OFFER, YOU MUST
      VALIDLY TENDER (AND NOT WITHDRAW) SUCH UNREGISTERED NOTES TO THE
                  EXCHANGE AGENT PRIOR TO THE EXPIRATION DATE.

                          SIGNATURES MUST BE PROVIDED
              PLEASE READ THE ACCOMPANYING INSTRUCTIONS CAREFULLY.
 


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                               DESCRIPTION OF TENDERED NOTES
- --------------------------------------------------------------------------------------------
                                                               CERTIFICATE      PRINCIPAL
       NAME(S) AND ADDRESS(ES) OF REGISTERED OWNER(S)           NUMBER(S)         AMOUNT
 AS THEY APPEAR ON THE UNREGISTERED 11% SENIOR SUBORDINATED      OF NOTES        OF NOTES
         NOTES DUE 2008 (PLEASE FILL IN, IF BLANK)               TENDERED        TENDERED
                                                                        
- --------------------------------------------------------------------------------------------
 
                                                              ------------------------------
 
                                                              ------------------------------
 
                                                              ------------------------------
 
                                                              ------------------------------
 
                                                              ------------------------------
 
                                                              ------------------------------
 
                                                              ------------------------------
                                                                  TOTAL
                                                                PRINCIPAL
                                                                  AMOUNT
                                                                 OF NOTES
                                                                 TENDERED
 
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                                       2

Ladies and Gentlemen:
 
    1. The undersigned hereby tenders to MEDIQ/PRN Life Support Services, Inc.,
a Delaware corporation (the "Company"), the 11% Senior Subordinated Notes due
2008 (the "Old Notes") described above pursuant to the Company's offer of $1,000
principal amount of 11% Senior Subordinated Notes due 2008 (the "New Notes"), in
exchange for each $1,000 principal amount of the Old Notes, upon the terms and
subject to the conditions contained in the Prospectus dated           , 1998
(the "Prospectus"), receipt of which is hereby acknowledged, and in this Letter
of Transmittal (which together constitute the "Exchange Offer").
 
    2. The undersigned hereby represents and warrants that it has full authority
to tender the Old Notes described above. The undersigned will, upon request,
execute and deliver any additional documents deemed by the Company to be
necessary or appropriate to complete the tender of Old Notes.
 
    3. The undersigned understands that the tender of the Old Notes pursuant to
all of the procedures set forth in the Prospectus will constitute an agreement
between the undersigned and the Company as to the terms and conditions set forth
in the Prospectus.
 
    4. Unless the box under the heading "Special Registration Instructions" is
checked, the undersigned hereby represents and warrants that:
 
        (i) the New Notes acquired pursuant to the Exchange Offer are being
    acquired in the ordinary course of business of the undersigned, whether or
    not the undersigned is the holder of the Old Notes;
 
        (ii) neither the undersigned nor any such other person has an
    arrangement or understanding with any person to participate in the
    distribution of such New Notes or Old Notes within the meaning of the
    Securities Act of 1933, as amended (the "Securities Act");
 
        (iii) neither the undersigned nor any such other person is an
    "affiliate," as such term is defined under Rule 405 promulgated under the
    Securities Act, of the Company or any of the guarantors of the New Notes or
    the Old Notes (the "Guarantors"), or if it is an affiliate, the undersigned
    or such other person will comply with the registration and prospectus
    delivery requirements of the Securities Act to the extent applicable;
 
        (iv) if the undersigned or such other person is not a broker-dealer,
    neither the undersigned nor any such other person is engaged in or intends
    to engage in the distribution of such New Notes; and
 
        (v) if the undersigned or such other person is a broker-dealer, neither
    the undersigned or such other person will receive New Notes for its own
    account in exchange for Old Notes that were acquired as the result of
    market-making activities or other trading activities.
 
    5. The undersigned may, IF, AND ONLY IF, UNABLE TO MAKE ALL OF THE
REPRESENTATIONS AND WARRANTIES CONTAINED IN ITEM 4 ABOVE, elect to have its Old
Notes registered in the shelf registration described in the Registration Rights
Agreement, dated May 21, 1998, among the Company, the Guarantors, MEDIQ
Incorporated, a Delaware corporation and the parent corporation of the Company
("Holdings"), and the initial purchasers of the Old Notes (the "Registration
Rights Amendment;" all capitalized terms used in this Item 5, unless otherwise
defined herein, shall have the meanings given them in the Registration Rights
Agreement), a conformed copy of which has been filed as an exhibit to the
Registration Statement of which the Prospectus constitutes a part. Such election
may be made by checking the box under "Special Registration Instructions." By
making such election, the undersigned agrees, as a holder of Transfer Restricted
Securities participating in a shelf registration, to indemnify and hold harmless
the Company, the Guarantors, their respective directors and officers and each
person, if any, who controls the Company or any of the Guarantors within the
meaning of either Section 15 of the Securities Act or Section 20 of the
Securities Exchange Act of 1934, as amended (the "Exchange Act"), from and
against any losses, claims, damages or liabilities, joint or several, or any
actions in respect thereof (including, but not limited to, any losses, claims,
damages, liabilities or actions relating to
 
                                       3

purchases and sales of the New Notes) to which the Company, any Guarantor,
Holdings or any such director, officer or controlling person may become subject
under the Securities Act, the Exchange Act or otherwise, insofar as such losses,
claims, damages, liabilities or actions arise out of, or are based upon, any
untrue statement or alleged untrue statement of a material fact contained in a
registration statement or prospectus or in any amendment or supplement thereto
or in any preliminary prospectus relating to a shelf registration, or arise out
of, or are based upon, the omission or alleged omission to state therein a
material fact or necessary to make the statements therein not misleading, but in
each case only to the extent that the untrue statement or omission or alleged
untrue statement or omission was made in reliance upon and in conformity with
written information pertaining to the undersigned and furnished to the Company
by or on behalf of the undersigned specifically for inclusion therein. Any such
indemnification shall be governed by the terms and subject to the conditions set
forth in the Registration Rights Agreement, including, without limitation, the
provisions regarding notice, retention of counsel, contribution and payment of
expenses set forth therein. The above summary of the indemnification provisions
of the Registration Rights Agreement is not intended to be exhaustive and is
qualified in its entirety by reference to the Registration Rights Agreement.
 
    6. If the undersigned is a broker-dealer that will receive New Notes for its
own account in exchange for Old Notes that were acquired as a result of
market-making activities or other trading activities, it acknowledges that it
will deliver a prospectus in connection with any resale of such New Notes;
however, by so acknowledging and delivering a prospectus, the undersigned will
not be deemed to admit that it is an "underwriter" within the meaning of the
Securities Act. If the undersigned is a broker-dealer and Old Notes held for its
own account were not acquired as a result of market-making or other trading
activities, such Old Notes cannot be exchanged pursuant to the Exchange Offer.
 
    7. Any obligation of the undersigned hereunder shall be binding upon the
successors, assigns, executors, administrators, trustees in bankruptcy and legal
and personal representatives of the undersigned.
 
    8. Unless otherwise indicated herein under "Special Delivery Instructions,"
the certificates for the New Notes will be issued in the name of the
undersigned.
 
                                       4

                         SPECIAL DELIVERY INSTRUCTIONS
                              (SEE INSTRUCTION 1)
 
    To be completed ONLY IF the New Notes are to be issued or sent to someone
other than the undersigned or to the undersigned at an address other than that
provided above.
 
        Mail / /  Issue / /  (Check appropriate boxes) certificates to:
 
Name: __________________________________________________________________________
                                 (Please Print)
 
Address: _______________________________________________________________________
 
                                         _______________________________________
 
                                         _______________________________________
 
                              (Including Zip Code)
 
                       SPECIAL REGISTRATION INSTRUCTIONS
                                  (SEE ITEM 5)
 
    To be completed ONLY IF (i) the undersigned satisfies the conditions set
forth in Item 5 above, (ii) the undersigned elects to register its Old Notes in
the shelf registration described in the Registration Rights Agreement, and (iii)
the undersigned agrees to indemnify certain entities and individuals as set
forth in the Registration Rights Agreement and summarized in Item 5 above.
 
    / /  By checking this box the undersigned hereby (i) represents that it is
unable to make all of the representations and warranties set forth in Item 4
above, (ii) elects to have its Old Notes registered pursuant to the shelf
registration described in the Registration Rights Agreement, and (iii) agrees to
indemnify certain entities and individuals identified in, and to the extent
provided in, the Registration Rights Agreement and summarized in Item 5 above.
 
                       SPECIAL BROKER-DEALER INSTRUCTIONS
                                  (SEE ITEM 6)
 
    / /  Check here if you are a broker-dealer and wish to receive 10 additional
copies of the Prospectus and 10 copies of any amendments or supplements thereto.
 
Name: __________________________________________________________________________
                                 (Please Print)
 
Address: _______________________________________________________________________
 
                                         _______________________________________
 
                                         _______________________________________
 
                              (Including Zip Code)

                                   SIGNATURE
 
    To be completed by all exchanging noteholders. Must be signed by the
registered holder exactly as such holder's name appears on the Old Notes. If the
signature is by a trustee, executor, administrator, guardian, attorney-in-fact,
officer of a corporation or other person acting in a fiduciary or representative
capacity, please set forth such person's full title. See Instruction 3.
 
X ______________________________________________________________________________
 
X ______________________________________________________________________________
          Signature(s) of Registered Holder(s) or Authorized Signature
 
Dated: _________________________________________________________________________
 
Name(s): _______________________________________________________________________
 
________________________________________________________________________________
                             (Please Type or Print)
 
Capacity: ______________________________________________________________________
 
Address: _______________________________________________________________________
 
                                         _______________________________________
 
                                         _______________________________________
                              (Including Zip Code)
 
Area Code and Telephone No.: ___________________________________________________
 
               SIGNATURE GUARANTEE (IF REQUIRED BY INSTRUCTION 1)
        CERTAIN SIGNATURES MUST BE GUARANTEED BY AN ELIGIBLE INSTITUTION
 
                                        ________________________________________
             (Name of Eligible Institution Guaranteeing Signatures)
 
________________________________________________________________________________
  (Address (including zip code) and Telephone Number (including area code) of
                                     Firm)
 
________________________________________________________________________________
                             (Authorized Signature)
 
________________________________________________________________________________
                                 (Printed Name)
 
________________________________________________________________________________
                                    (Title)
 
Dated: _________________________________________________________________________

                      PLEASE READ THE INSTRUCTIONS BELOW,
                WHICH FORM A PART OF THIS LETTER OF TRANSMITTAL.
                                  INSTRUCTIONS
 
    1. GUARANTEE OF SIGNATURES. Signatures on this Letter of Transmittal must be
guaranteed by an eligible guarantor institution that is a member of or
participant in the Securities Transfer Agents Medallion Program, the New York
Stock Exchange Medallion Signature Program, the Stock Exchange Medallion
Program, or by an "eligible guarantor institution" within the meaning of Rule
17Ad-15 promulgated under the Exchange Act (an "Eligible Institution") unless
the box entitled "Special Registration Instructions" or "Special Delivery
Instructions" above has not been completed or the Old Notes described above are
tendered for the account of an Eligible Institution.
 
    2. DELIVERY OF LETTER OF TRANSMITTAL AND OLD NOTES. The Old Notes, together
with a properly completed and duly executed Letter of Transmittal (or copy
thereof), should be mailed or delivered to the Exchange Agent at the address set
forth above.
 
    THE METHOD OF DELIVERY OF OLD NOTES AND THE LETTER OF TRANSMITTAL AND ALL
OTHER REQUIRED DOCUMENTS TO THE EXCHANGE AGENT IS AT THE ELECTION AND RISK OF
THE HOLDER. INSTEAD OF DELIVERY BY MAIL, IT IS RECOMMENDED THAT HOLDERS USE AN
OVERNIGHT OR HAND DELIVERY SERVICE. IN ALL CASES, SUFFICIENT TIME SHOULD BE
ALLOWED TO ENSURE DELIVERY TO THE EXCHANGE AGENT BEFORE THE EXPIRATION DATE. NO
LETTER OF TRANSMITTAL OR OLD NOTES SHOULD BE SENT TO THE COMPANY. HOLDERS MAY
REQUEST THEIR RESPECTIVE BROKERS, DEALERS, COMMERCIAL BANKS, TRUST COMPANIES, OR
NOMINEES TO EFFECT THE ABOVE TRANSACTIONS FOR SUCH HOLDERS.
 
    3. SIGNATURE ON LETTER OF TRANSMITTAL, BOND POWERS AND ENDORSEMENTS. If this
Letter of Transmittal is signed by a person other than a registered holder of
any Old Notes, such Old Notes must be endorsed or accompanied by appropriate
bond powers, signed by such registered holder exactly as such registered
holder's name appears on such Old Notes.
 
    If this Letter of Transmittal or any Old Notes or bond powers are signed by
trustees, executors, administrators, guardians, attorneys-in-fact, officers of
corporations, or others acting in a fiduciary or representative capacity, such
persons should so indicate when signing, and, unless waived by the Company,
proper evidence satisfactory to the Company of their authority to so act must be
submitted with this Letter of Transmittal.
 
    4. MISCELLANEOUS. All questions as to the validity, form, eligibility
(including time of receipt), acceptance, and withdrawal of tendered Old Notes
will be determined by the Company in its sole discretion, which determination
will be final and binding on all parties. The Company reserves the absolute
right to reject any or all Old Notes not properly tendered or any Old Notes the
Company's acceptance of which would, in the opinion of counsel for the Company,
be unlawful. The Company also reserves the right to waive any defects,
irregularities, or conditions of tender as to the particular Old Notes. The
Company's interpretation of the terms and conditions of the Exchange Offer
(including the instructions in this Letter of Transmittal) will be final and
binding. Unless waived, any defects or irregularities in connection with tenders
of Old Notes must be cured within such time as the Company shall determine.
Neither the Company, the Exchange Agent, nor any other person shall be under any
duty to give notification of defects in such tenders or shall incur any
liability for failure to give such notification. Tenders of Old Notes will not
be deemed to have been made until such defects or irregularities have been cured
or waived. Any Old Notes received by the Exchange Agent that are not properly
tendered and as to which the defects or irregularities have not been cured or
waived will be returned by the Exchange Agent to the tendering holder thereof as
soon as practicable following the Expiration Date.