&lt;p&gt;During a fire the ceiling cavity can allow fire or smoke to&lt;br /&gt;spread throughout a building. To inhibit fire entering the&lt;br /&gt;cavity via the ceiling loudspeaker it can be fitted with an&lt;br /&gt;LBC 3080/01 steel fire dome. This is mounted on the&lt;br /&gt;loudspeaker assembly using four self-tapping screws&lt;br /&gt;supplied with the fire dome. The fire-dome has knockout&lt;br /&gt;holes for two grommets (supplied) and two cable glands.&lt;br /&gt;This fire dome can only be used with the ceiling speakers:&lt;br /&gt;LBC 3087/41 LBC 3090/01 LBC 3090/31 LHM 0606/00&lt;br /&gt;and LHM 0606/10.&lt;br /&gt;&lt;/p&gt;