Item dislodged during a seismic event will be contained within the walls of ACU ?

[strainstress]

Hello,

I am working on seismic qualification of an Air Conditioning Unit. The internal components of the ACU (fan, coils, filter, damper actuators etc) can fail structurally during the seismic event, as long as they are contained within the ACU. The walls of the ACU is 2" thick (14Ga sheet inside and 20 ga outside with a thermal insulation in between).

How do I go about proving that even if the internal components dislodge during a seismic event, they will be contained within the unit ?

I understand that perforation through a wall is very tricky problem and depends on a lot of factors, like velocity of impact, angle of impact, area of impact etc. Is there any lower bound solution that could be used to reasonably justify that items will be contained within the unit (I have seen BRL formula for steel plates, formula depends on the diameter and velocity of impact, but I could not find the limits of the applicability of this BRL formula anywhere)

Thanks
StrainStress

 

[GearsNsparks]

To get a seismic certification for your ACU don't you have to qualify it on a shake table? I would think running it on a shake table provides much more certainty than trying to calculate what would happen.

 

[wannabeSE]

I have only seen shake table results for this type of equipment. You might be interested at looking at some of OSHPD's Special Seismic Certification Preapproval OSP (OSP) reports on their website at:

http://www.oshpd.ca.gov/fdd/Pre-Approval/special_seismic_cert_pre-approval.html.