EXHIBIT 5

                               MCBRIDE BAKER & COLES
                              500 WEST MADISON STREET
                                     40TH FLOOR
                              CHICAGO, ILLINOIS  60661



                                  March 26, 1998



The Board of Directors of
Hach Company
5600 Lindbergh Drive
Loveland, Colorado  80537

     Re:   REGISTRATION STATEMENT ON FORM S-4

Ladies and Gentlemen:

     We have acted as legal counsel for Hach Company, a Delaware corporation 
(the "Company"), in connection with the Company's preparation of the 
above-referenced is made to the form of the Registration Statement on Form 
S-4 to be filed with the Securities and Exchange Commission (the 
"Commission") on or about March 26, 1998 (the "Registration Statement"), 
under the Securities Act of 1933, as amended (the "Act") and the proxy 
statement/prospectus included therein (the "Proxy Statement/Prospectus").  
The Registration Statement and Proxy Statement/Prospectus relate to the 
registration by the Company of up to 755,645 shares of Common Stock and 
331,543 shares of Class A Common Stock of the Company (collectively, the 
"Shares"), which will be issuable to holders of capital stock of 
Environmental Test Systems, Inc., an Indiana corporation ("ETS"), in the 
proposed merger (the "Merger") of a wholly-owned subsidiary of the Company 
with and into ETS pursuant to an Agreement and Plan of Merger dated as of 
January 21, 1998.  At your request, this opinion is being furnished to you 
for filing as EXHIBIT 5 to the Registration Statement.

     In connection herewith, we have examined:  (i) the Form S-4 and the 
Proxy Statement/Prospectus; (ii) the Amended and Restated Certificate of 
Incorporation, as amended, and the Bylaws as amended, of the Company; (iii) 
the corporate minutes and proceedings of the Company applicable to filing of 
the Form S-4; (iv) such other proceedings, documents and records as we deem 
necessary or appropriate for the purpose of making this opinion.  In making 
such examinations, we have assumed the genuineness of all signatures on all 
documents and conformed originals to all copies submitted to us as conformed 
or photocopies.



     In addition to such examination, we have ascertained or vertified such 
additional facts as we deem necessary or appropriate for purposes of this 
opinion.  However, as to various questions of fact material to our opinion, 
we have relied upon representations, statements or certificates of officers, 
directors, or representatives of the Company or others.

     Based upon the foregoing examination, and in reliance thereon, we are of 
the opinion that 

     1.  The Company has been legally incorporated and is validly 
existing under the laws of the State of Delaware; and 

     2.  When the conditions to the transactions contemplated by the Merger 
Agreement shall have been satisfied or waived and the Registration Statement 
has become effective, and subject to the terms of the Company's Common Stocks 
being otherwise in compliance with applicable law, then all Shares issuable 
on the effectiveness of the Merger will be legally issued, fully paid and 
non-assessable shares of Common Stocks of the Company.

     The foregoing opinion is subject to (i) any applicable bankruptcy, 
insolvency, reorganization, moratorium or similar laws affecting creditors' 
rights generally and (ii) with respect to the enforceability of any agreement 
to general principles of equity (regardless of whether such enforceability is 
considered in an action at law or in equity).

     We are qualified to practice law in the State of Illinois and do not 
purport to be an expert on, or to express any opinion herein concerning any 
law other than the laws of the State of Illinois, the corporation laws of the 
State of Delaware, and the federal laws of the United States.  Without 
limiting the generality of the foregoing, we express no opinion as to the 
effect of the law of any jurisdiction other than the State of Illinois or the 
corporate law of Delaware.  

     We hereby consent to the filing of this opinion as an exhibit to the 
Registration Statement, and we further consent to the use of our name under 
the caption "LEGAL MATTERS" in the Proxy Statement/Prospectus.  In giving 
this consent we do not admit that we have come within the category of persons 
whose consent is required under Section 7 of the Act or the Rules or 
Regulations of the Commission promulgated thereunder.

                                       Very truly yours,

                                       MCBRIDE BAKER & COLES