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H2 or H3?

E

earshavewalls

Bronze Member
Joined
Oct 21, 2009
Messages
77
Location
Southern California
We are preparing for review of a nitrate film storage and restoration facility. They will be handling, storing, and restoring film that was made prior to 1951. They will definitely have more quantity than is allowed in a B occupancy. We are under the 2007 California Building Code and all other California Codes. We are not quite certain if this will be an H2 or an H3 occupancy.....

Nitrate Cellulose Film becomes highly unstable as it decomposes, based on five different levels of decomposition. The facility in question will be inspecting all films brought in and will determine if they are salvageable or not. No film that is unsalvageable will be kept or worked on; it will just be properly disposed of. The issue is that when the film is past stage 4 it becomes an explosion hazard but prior to that stage, it is only highly flammable instead of a detonation hazard. We would like to classify this building as H3, but thought we would test the waters for any possible reasons NOT to allow it as an H3.

Any comments will be appreciated.

Thanks,

Wayne
 
Re: H2 or H3?

I would rely on NFPA 40 Standard for the Storage and Handling of Cellulose Nitrate Film as a starting point. It is a reference Standard in IBC Chapter 35.
 
Re: H2 or H3?

Thanks for the input, but I have already researched NFPA 40. It does not indicate which classification to put the occupancy into. The issue is the state of the film as it comes in and the state of the film that is kept to be transferred onto safety film and then put into specific storage vaults for long term storage of this film.

Our dilemna is whether to consider the film as "unstable (reactive) materials, Class 3, nondetonable", which puts it into an H-2 occupancy (CBC 307.4)...............OR...............if the film in this state is "unstable (reactive) materials, Class 2".

H-2 materials are considered a deflagration hazard or a hazard from accelerated burning.

H-3 materials are considered as readily supporting combustion or pose a physical hazard.

H-3 is less restrictive and may work for the intended use, but we have doubts. H-2 would not work for what they have in mind.

The problem is that they wish to have all areas where the film is handled, worked on, and stored to be on the first level and that the level above would be only offices. The difficulty with this is CBC 415.5, which states that H-2 and H-3 occupancies "shall be in buildings used for no other purpose, shall not exceed one story in height and shall be without basements, crawl spaces or other under-floor spaces. Well.....there is an interstitial space for mechanical equipment between the lower level and the upper level. We are afraid that this design is not compliant and that they may be required to remove the second floor offices in order to comply.

This is an extremely high profile project. The films to be stored here are classics and are not replaceable. We want to assist the project as much as possible, but I'm afraid that we may have some difficulties in accommodating their design wishes.

Now, any further comments? We are still looking for a way, within the codes, to permit this building, so any guidance that we have not considered would be appreciated.

Thanks,

WW
 
Re: H2 or H3?

"that the level above would be only offices"......... :lol:

Sorry, just couldn't stop myself but don't see how they can do that. My recommendation would be to have them pay for a Performance Design if they are hard fast for offices above the H-2. The reason I say H-2 is that when there are any potentials to have unstable materials, I ALWAYS error on the worst case as permitted. Explaining the potential hazards to them and asking them to hire an FPE to run some PD's and come up with one that could be considered is not being non-customer service friendly just protecting the extreemly hazardous situation they are about to embark on.....JMHO.
 
William,

This facility has two phases. The higher risk film (film that is at stage 4 or 5 of decomposition) will be destroyed and all film that comes to the facility will go through the Phase 1 building (completed 3 years ago), which IS an H-2. We have finally determined that we will classify the labs where the film (only stages 1, 2, and 3) will be restored and copied onto safety film as H-3, since it is NOT considered Unstable (reactive) until it reaches stages 4 and 5, it is highly flammable, though. This keeps it in the realm of H-3.

The real problem is the fact that H-3 occupancies are required to be no more than 1-story. This proposed building is two stories (only one story completely above grade) with an interstitial space between floors to house the specialized venting and HVAC for these areas. THIS is the potential "Deal Breaker" for this design. I am now looking for any code justification that would allow this building to have the H-3 below (with "B" offices across the 1-hour rated corridor).........these "B" offices are to be used by the technicians who restore the films. As they transfer them to digital images, they use the computers in the offices across the hall to enhance and digitally re-master these films. They are then transferred to safety film (if theatrical) or kept in digital format and the original cellulose film will go back into the vaults in Phase 1.

It is quite a project, and quite high on the political radar, too. A major film studio and University are working together on this one, so there are lots of "eyes" on it. We want to be absolutely certain if we are going to tell them that a complete redesign will need to be performed, so I am looking under every rock, bush, and book that I can to make sure that there isn't an exception or something that I am missing here.

These folks have been to this "dance" before and are quite aware of all potential hazards with this facility. They have a fire protection "expert" on their team and he is a fast talker and wanted answers "yesterday"..........so a few red flags went up. We will not let this go out until we are sure that it is right, but again, we want to be absolutely certain.

Thanks for your input! The value of this project is upward of $20 million. (Good to see SOMEONE has money to spend!)

Thanks,

Wayne
 
Do you need substantiating data to reinforce the fact that cellulose nitrate is really nothing more than pseudo "flammable solid?" I'm unsure what you are wanting. The building is sprinklered and your samples are most likely small given that it's old film. I understand the code implications but your post doesn't explicitly ask a question.
 
Get your second story

Install control areas that that have less than the maximum allowed quantity stored, a fire sprinklered systems is part of the proposal. This would allow the second story.
 
I'd probably go with H-3, combustible solid.

Didn't ICC used to specifically classify nitrate film? (Maybe it was SBCCI).
 
Thanks to all who responded. We have ammassed a large amount of information on the subject and will be working directly with the design professionals as well as their consultants to make sure we approve the right stuff. This is an extremely specialized occupancy with many issues that need to be addressed; more than is typical.

This is the interesting part of this job!
 
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