If you are going to install sprinklers then maybe this information is of help.
We recently prepared an in the dome wet design for the same except that the dome diameter was considerably smaller. First of all the space above the dome is noncombustible, so there were no sprinklers above the dome. This is an existing dome in a university setting. White flat coverplates (already fused) were shipped out to the owner with a layuut plan and instructions to try one to see if the coverplate caused any image problems. We were told to go ahead with the concept. The sprinkler layout is based upon LH and is using the actual distance along the dome curve to verfiy that the layout did not technically exceed NFPA 13 spacing rules. The dome curve was also checked to see if it is an obstruction to discharge. as it turned out the curve radius was tight enough to obstruct discharge for an extended coverage sprinkler. This may not be a problem for a 30 foot radius but the sprinkler would have to be a flat coverplate EC. The space outside of the dome is painted out black. There is considerable light leakage through the perforated dome. I witnessed this myself. The dome actually appears as a lighted surface when viewed from its backside. The sprinkler will be installed with a black sheet metal shroud covering the sprinkler parts that are outside of the dome. This includes the last fitting to which the shroud will attach. The intent is to have nothing that can reflect light back into the dome. The piping will be painted out black. Each sprinkler will terminate at back to back 90s and sit at the end of a vertical drop. For this dome there are only four sprinklers located near the top of the dome. The project location is not in a seismic area. Allan Seidel St. Louis, MO On Tue, Sep 9, 2008 at 9:24 PM, George Lau <[EMAIL PROTECTED]> wrote: > Dear Sprinkler Experts, > > I am new to the forum. Besides a "Hi" to yall, I am desperately seeking > suggestion or reference regarding the "Sprinkler installation in a > PLANETARIUM" which possesses a (60ft dia) semi-spherical dome screen (made > of white paint coated matellic plate with small holes). Our current plan is > to keep all those sprinker heads above the dome screen. Is it a workable > design? > > Since we are lack of local technical reference, can anyone throw me some > light regarding the normal practice, if the sprinkler heads should be above > the dome screen. If yes, what other concerns/attention should be paid? > > Thank you so much, > George Lau > Macau S.A.R. > > > > > _______________________________________________ > Sprinklerforum mailing list > http://lists.firesprinkler.org/mailman/listinfo/sprinklerforum > For Technical Assistance, send an email to: [EMAIL PROTECTED] > > To Unsubscribe, send an email to:[EMAIL PROTECTED]<[EMAIL PROTECTED]> > (Put the word unsubscribe in the subject field) > _______________________________________________ Sprinklerforum mailing list http://lists.firesprinkler.org/mailman/listinfo/sprinklerforum For Technical Assistance, send an email to: [EMAIL PROTECTED] To Unsubscribe, send an email to:[EMAIL PROTECTED] (Put the word unsubscribe in the subject field)
