In Ontario building code SB-2:
2.3.3. Limitations of Component Additive Method
...
(2) The assigned times in Sentences 2.3.4.(2) to (4) are not intended to be construed as the fire-resistance ratings of the
individual components of an assembly, nor are they intended to be construed as times that are applicable or acceptable for
use beyond the method and systems described in this Subsection. These assigned times are the individual contributions of
each component to the overall fire-resistance rating of an assembly, which are permitted to be derived using the
component additive method described in this Subsection.
1st question:
1. What does "for use beyond the method and systems described in this Subsection" mean?
According to the following text from this link: https://kilolimacode.com/component-additive-method-for-fire-resistance-ratings/ fire-resistance rating of an assembly is not the sum of the times assigned to individual components, then my 2nd question:
2. Fire-resistance rating of an assembly is what is used in fire protection design, is there any practical use of the component additive method, as it doesn't derive the assembly fire resistance rating? If there is no, why is it in the code?
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3. Times assigned are not the fire-resistance ratings of individual components
...
The times assigned to membranes in the CAM are not the same as “finish ratings” sometimes cited in listings. The times assigned to membranes are based primarily on their ability to remain in place during fire tests. A fire-resistance rating, however, also includes a temperature rise limitation criteria. The temperature rise criteria is not accounted for in the times assigned to components in Appendix D, as it relies upon the entire assembly to meet the criteria. Finish ratings provided on listings account for the temperature rise criteria and can be considered as the fire-resistance rating provided by the finish/membrane only in an assembly.
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2.
2.3.3. Limitations of Component Additive Method
...
(2) The assigned times in Sentences 2.3.4.(2) to (4) are not intended to be construed as the fire-resistance ratings of the
individual components of an assembly, nor are they intended to be construed as times that are applicable or acceptable for
use beyond the method and systems described in this Subsection. These assigned times are the individual contributions of
each component to the overall fire-resistance rating of an assembly, which are permitted to be derived using the
component additive method described in this Subsection.
1st question:
1. What does "for use beyond the method and systems described in this Subsection" mean?
According to the following text from this link: https://kilolimacode.com/component-additive-method-for-fire-resistance-ratings/ fire-resistance rating of an assembly is not the sum of the times assigned to individual components, then my 2nd question:
2. Fire-resistance rating of an assembly is what is used in fire protection design, is there any practical use of the component additive method, as it doesn't derive the assembly fire resistance rating? If there is no, why is it in the code?
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3. Times assigned are not the fire-resistance ratings of individual components
...
The times assigned to membranes in the CAM are not the same as “finish ratings” sometimes cited in listings. The times assigned to membranes are based primarily on their ability to remain in place during fire tests. A fire-resistance rating, however, also includes a temperature rise limitation criteria. The temperature rise criteria is not accounted for in the times assigned to components in Appendix D, as it relies upon the entire assembly to meet the criteria. Finish ratings provided on listings account for the temperature rise criteria and can be considered as the fire-resistance rating provided by the finish/membrane only in an assembly.
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2.