Gas-fired construction heaters

1.1  
This Standard applies to newly produced, direct-fired and indirect-fired construction heaters, hereinafter 
referred to as heaters or appliances, constructed entirely of new, unused parts and materials and primarily 
intended for temporary use in heating buildings or structures under construction, alteration, or repair. All the 
products of combustion generated by the direct-fired heater are released into the area being heated. Products 
of combustion for indirect-fired heaters are vented to the outdoors. The requirements of this Standard cover 
heaters with rated inputs up to and including 10,000,000 BTU/h (2930 kW). 
1.2  
This Standard applies to self-contained heaters with or without integral means for air circulation and may be 
intended for connection to ducts.  
If a heater is designed to be utilized with ductwork, the heater is to be tested with the ductwork recommended 
by the manufacturer or at the maximum static pressure specified by the manufacturer. 
1.3  
This Standard does not apply to heaters for use with liquid phase fuel gases, except where the heater is for 
use with liquid propane and incorporates an integral vaporizer that meets the requirements per Clause 7. 
Heaters for use with liquid propane shall meet the requirements for heaters for outdoor use per Clause 5.14. 
1.4  
This Standard applies to direct ground thawing appliances for outdoor use where heat is directed into the 
ground. 

1.5  
This Standard applies to universal construction heaters (see Clause 3, Definitions) intended for use with either 
natural or propane gases. 
1.6  
This Standard applies to heaters using the following fuels: 
a) natural gas; and 
b) propane gas. 
1.7  
This Standard does not apply to heaters employing a flameless catalytic combustion process or heaters for 
use with liquid phase fuel gases. 
1.8  
If a value for measurement as given in this Standard is followed by an equivalent value in other units, the first 
state value is to be regarded as the specification. 
1.9  
All accessories intended for use with appliances certified to this Standard are to be tested on the appliance in 
which they may be used. 
1.10  
Annex A, Items unique to Canada, contains items unique to the Canada. 
1.11  
Annex B, Items unique to the United States, contains items unique to the U.S. 
1.12  
Special construction provisions applicable to an appliance designed for use with an optional listed conversion 
kit are outlined under Annex D, (Optional) Provisions for Listed Gas Appliances Conversion Kits. 
1.13  
Clause 2 contains a list of standards specifically referenced in this Standard, and sources from which these 
reference standards may be obtained. 
1.14  
All references to psi throughout this Standard are to be considered gauge pressure unless otherwise specified. 
1.15  
This Standard contains SI (Metric) equivalents to the yard/pound quantities, the purpose being to allow the 
Standard to be used in SI (Metric) units. (IEEE/ASTM SI 10, American National Standard for Metric Practice, 
or ISO 80000-1:2009, Quantities and units – Part 1: General is used as a guide in making metric conversion 
from yard/pound quantities.) If a value for a measurement and a corresponding value in other units are stated, 
the first stated value is to be regarded as the requirement. The given corresponding value may be 
approximate. If a value for a measurement and a corresponding value in other units are both specified as a 
quoted marking requirement, the first stated unit, or both are to be provided. 

1.16  
In this Standard, “shall” is used to express a requirement, i.e., a provision that the user shall satisfy in order to 
comply with the standard; “should” is used to express a recommendation or that which is advised but not 
required; and “may” is used to express an option or that which is permissible within the limits of the standard. 
Notes accompanying clauses do not include requirements or alternative requirements; the purpose of a note 
accompanying a clause is to separate from the text explanatory or informative material. 
Notes to tables and figures are considered part of the table or figure and may be written as requirements. 
Annexes are designated normative (mandatory) or informative (non-mandatory) to define their application.