SFPE Discussions

New C/AS2, C/VM2 out

There is a shiny new C/AS2, C/VM2 and C/AS1 (houses) out on the MBIE website for those who have not seen it yet.

https://www.building.govt.nz/building-code-compliance/c-protection-from-fire/c-clauses-c1-c6/acceptable-solutions-and-verification-methods/

Note the facade compliance changes, especially for systems using NFPA285 as a means of compliance.

Seen it and disappointed that the obvious errors have not been fixed to make it a better document and also confused in respect of some changes and why MBIE have gone there…take a look at the horizontal fire spread tables…:frowning:

Haven’t been through the docs in any detail but something seems very wrong with C/AS2 Table 5.2x and 5.3x that’s for sure.

The use of NFPA285 tests to comply with vertical fire spread requirements seems a bit inconsistent. The standard is reportedly updated - 2019 version - to permit tests with timber framing, but the requirements - in C/VM2 and the MBIE Cladding Guidance state that this standard can only be used to demonstrate compliance if all the components (implied to include wall framing) are non- or limited combustible, or Type A - which effectively excludes timber framing.

Suggest a comment is also passed to MBIE regarding the extremely poor quality of C/AS2 Figure 4.5 on page 97.

The text in the image is barely discernable.
Even in the reissued amendment 2 today…

Is anyone aware of what was intended with the change to C/AS2 Paragraph 3.7.1 (formerly 3.7.13), for passing into an adjacent firecell?

The difference I see is that it now implies any escape route (including a safe path?) can continue as an open path once it reaches an adjacent firecell, whereas before this was limited to open paths only. Moving from a safe path to an open path would contradict the principle of never passing from a higher level to a lower level of protection, as required by Paragraph 3.1.2. Am I missing something here?

New version:
3.7.1 If an escape route passes through a
number of fire separations it is permitted
to continue as an open path provided the
cumulative travel distance does not exceed
the permitted distance specified in Table 3.2.

Old Version:
3.7.13 If an open path passes through a
number of fire separations it is permitted to
continue as the same open path provided
the cumulative travel distance does not
exceed the permitted distance specified in
Table 3.2.

yes pointed it out to MBIE and they changed it.