GA vs. UL assembly

[Sifu]

Out of curiosity, why would a designer specify a GA assembly instead of a UL assembly? For example, GA wp3269 is specified, which has fire test UL design U341. Why specify wp3269 and not U341?

 

[redeyedfly]

Because they opened up their GA manual first

 

[Yikes]

The UL assemblies only show fire test ratings.
The GA has both fire and sound test ratings.

 

[jc_ks]

Perhaps the GA assembly has a noise rating in addition to the fire rating

 

[RLGA]

This:

The UL assemblies only show fire test ratings.
The GA has both fire and sound test ratings.

Plus, it is easier to visually scan and read compared to UL’s Product iQ.

 

[Sifu]

Rare to agree with everybody, but I do. I can find no good reason why out of the dozens of systems submitted, only a few were GA, the rest were straight UL. The GA's do have the sound testing, and that is a big part of the program so I was thinking that would be it. And I completely agree, reading UL systems is more difficult, and the GA manual I have is a very quick and easy book to navigate. Just was curious if there was some reason less obvious.

 

[Yikes]

Correct me if I'm wrong, but the listings in the UL catalogs only include fire tests by UL-approved labs, whereas the GA catalog can include fire tests by other organizations, such as Factory Mutual (FM)

 

[Sifu]

Correct me if I'm wrong, but the listings in the UL catalogs only include fire tests by UL-approved labs, whereas the GA catalog can include fire tests by other organizations, such as Factory Mutual (FM)

Well, since you bring it up....The fire test was where this question originated.

I have a dryer box in a rated wall. They provide a tested system, and it is tested "of the materials and in the manner specified in the UL individual U300, U400,, V400, or W400 series wall or partition designs in the UL Fire Resistance Directory". They propose it in a wall with a GA assembly, specifically WP 3269. Per the GA 3269 assembly, it is based on UL fire test UL U341. So when I got to looking at this is when I started to wonder why they chose the GA assembly and not the U341 , which as designed are the exact same. As I worked this through this, I decided (though not sure correctly) since the GA assembly was based on U341 and used the "materials and manner specified" in the UL design, that the dryer box for use in U341 met the criteria in the UL penetration system for the dryer box. So maybe I'm just lazy and wished they had just used the UL design as the wall assembly and saved me the time of thinking about it.

 

[steveray]

Well, since you bring it up....The fire test was where this question originated.

I have a dryer box in a rated wall. They provide a tested system, and it is tested "of the materials and in the manner specified in the UL individual U300, U400,, V400, or W400 series wall or partition designs in the UL Fire Resistance Directory". They propose it in a wall with a GA assembly, specifically WP 3269. Per the GA 3269 assembly, it is based on UL fire test UL U341. So when I got to looking at this is when I started to wonder why they chose the GA assembly and not the U341 , which as designed are the exact same. As I worked this through this, I decided (though not sure correctly) since the GA assembly was based on U341 and used the "materials and manner specified" in the UL design, that the dryer box for use in U341 met the criteria in the UL penetration system for the dryer box. So maybe I'm just lazy and wished they had just used the UL design as the wall assembly and saved me the time of thinking about it.

I'd be good with that, but most of the times the GA stuff I get does not have all of the information on the assembly construction, but maybe I have to look harder...

 

[Henchalwoog]

Doesn't the UL assemblies have duct / diffuser information (minimum truss depth for ducts)? I don't recall that being in the GA...

 

[ATX]

Generic GA assemblies may be preferred by an architect or designer because:

• per the footnotes at Tables 721.1 (1), 721.1(2), and 721.1(3) : Generic fire-resistance ratings (those not designated as PROPRIETARY* in the listing) in GA 600 shall be accepted as if herein listed. (So, they are accepted just like any other assembly listed in the tables)
• the GA general explanatory notes offer options, like the addition of glass fiber insulation in a wall that may not be possible using its UL counterpart along with the UL 263 Guide Info.

Regarding the use of sound data found in the GA manual, I follow the ICC G2-2010 Acoustics guidelines regarding reliable sources, which state:

• It is best to avoid reference sources where the focus is specific to fire ratings or other nonacoustical issues
• Avoid test summaries that do not include data at all the standard test frequencies.
• Avoid test summaries where the acoustical performance is summarized as a single-number rating within a range of other single-number ratings
  (e.g., STC 50-54).
• Etc.