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Key: (1) language to be deleted (2) new language


                         Laws of Minnesota 1991 

                        CHAPTER 331-S.F.No. 707 
           An act relating to public safety; modifying exceptions 
          to the requirement of inspection of boilers and 
          pressure vessels; amending Minnesota Statutes 1990, 
          sections 183.411, by adding a subdivision; and 183.56. 
    Section 1.  Minnesota Statutes 1990, section 183.411, is 
amended by adding a subdivision to read: 
    Subd. 1a.  [WAIVER.] A hobby boiler or show engine, not 
certified in Minnesota or any other jurisdiction, may be 
certified pursuant to the standards set out in subdivision 2.  
    The requirements of subdivision 2, paragraph (b), clause 
(1), for full radiographic examination of the long or 
longitudinal seam must be waived by the commissioner if:  
    (1) the other requirements of subdivision 2, paragraphs (b) 
and (c) are met; and 
    (2) the safety valve required by subdivision 2, paragraph 
(c), clause (2), is set at the maximum allowable working 
pressure determined consistent with the requirements of 
subdivision 2, paragraph (b), clause (2), or 100 pounds per 
square inch, whichever is lower, and if the maximum allowable 
working pressure is greater than 100 pounds per square inch, the 
owner of the boiler agrees with the lower safety valve setting. 
    Sec. 2.  Minnesota Statutes 1990, section 183.56, is 
amended to read: 
     183.56 [EXCEPTIONS.] 
    The provisions of sections 183.38 to 183.62, shall not 
apply to: 
    (1) boilers in buildings occupied solely for residence 
purposes with accommodations for not more than five families; 
    (2) railroad locomotives operated by railroad companies for 
transportation purposes; 
    (3) air tanks installed on the right-of-way of railroads 
and used directly in the operation of trains; 
    (4) boilers and pressure vessels under the direct 
jurisdiction of the United States; 
    (5) unfired pressure vessels having an internal or external 
working pressure not exceeding 15 p.s.i.g. with no limit on 
    (6) pressure vessels used for storage of compressed air not 
exceeding five cubic feet in volume and equipped with an 
American Society of Mechanical Engineers code stamped safety 
valve set at a maximum of 100 p.s.i.g.; 
    (7) pressure vessels having an inside diameter not 
exceeding six inches; 
    (8) pressure vessels with a nominal water containing 
capacity of 120 gallons or less for containing every vessel that 
contains water under pressure, including those containing 
air the compression of which that serves only as a cushion, 
whose design pressure does not exceed 300 p.s.i.g. and whose 
design temperature does not exceed 210 degrees Fahrenheit; 
    (9) boiler or pressure vessels located on farms used solely 
for agricultural or horticultural purposes; 
    (10) tanks or cylinders used for storage or transfer of 
liquefied petroleum gases; 
    (11) unfired pressure vessels in petroleum refineries; 
    (12) an air tank or pressure vessel which is an integral 
part of a passenger motor bus, truck, or trailer; 
    (13) hot water heating and other hot liquid boilers not 
exceeding a heat input of 750,000 BTU per hour; 
    (14) hot water supply boilers (water heaters) not exceeding 
a heat input of 500,000 BTU per hour, a water temperature of 210 
degrees Fahrenheit, a nominal water capacity of 120 gallons, or 
a pressure of 160 p.s.i.g.; 
    (15) a laundry and dry cleaning press not exceeding five 
cubic feet of steam volume; 
    (16) pressure vessels operated full of water or other 
liquid not materially more hazardous than water, if the vessel's 
contents' temperature does not exceed 140 degrees Fahrenheit or 
a pressure of 200 p.s.i.g.; and 
    (17) steam powered turbines at paper-making facilities 
which are powered by steam generated by municipal steam district 
facilities at a remote location.; and 
    (18) manually fired boilers for model locomotive, boat, 
tractor, stationary engine, or antique motor vehicles 
constructed or maintained only as a hobby for exhibition, 
educational or historical purposes and not for commercial use, 
if the boilers have an inside diameter of 12 inches or less, or 
a grate area of two square feet or less, and are equipped with 
an American Society of Mechanical Engineers stamped safety valve 
of adequate size, a water level indicator, and a pressure gauge. 
    An engineers license is not required for hot water supply 
    An engineers license is not required for boilers, steam 
cookers, steam kettles, steam sterilizers or other steam 
generators not exceeding 100,000 BTU per hour input, 25 
kilowatt, 2-1/2 horsepower or a pressure of 15 p.s.i.g.  
    Electric boilers not exceeding a maximum working pressure 
of 50 p.s.i.g., maximum of 30 kilowatt input or three horsepower 
rating shall be inspected as pressure vessels and shall not 
require an engineer license to operate. 
    Presented to the governor May 31, 1991 
    Signed by the governor June 4, 1991, 8:57 p.m.

Official Publication of the State of Minnesota
Revisor of Statutes