<?xml version="1.0" encoding="UTF-8" standalone="no"?><?Xpress productLine="ncc-clause" ?><clause id="_f7dbb28c-dc59-430b-9dd8-8dc4c95b9032" outputclass="ncc-clause"><meta><facet building="Class 1a"/><facet building="Class 1b"/><facet building="Class 10a"/><facet building="Class 10b"/><facet building="Class 10c"/></meta><sptc>S31C16</sptc><title id="_ae52c870-c331-45a3-af40-18cad96467a3">Smoke detection system</title><archive-num>2019: Spec G3.8: 4.2</archive-num><subclause id="_521bfbdf-2c9c-451a-9ec4-62e7c08509dd" outputclass="subclause"><title id="_7d854480-ee07-4f74-8d8c-1243d151de71">SubClause</title><num>1</num><p>Smoke detection within an <xref format="dita" href="/tmp/QppServer/Publishing/5e2c1f63-e589-4ce1-95e8-5c3e286a7aff/1197_1.0.0.xml#_d0042ee6-21cd-4d8c-8873-d8bfb694ceff" id="_944006eb-0964-4c0c-9aa8-545155c23a15" scope="local" type="abcb-glossentry">atrium</xref>—</p><ol outputclass="alpha"><li id="_44b9f7ea-237b-454d-9b1e-80ae1a7f0d48">must be provided within all outside air intakes and at individual floor return air intakes of all air-handling systems to initiate <xref format="dita" href="/tmp/QppServer/Publishing/5e2c1f63-e589-4ce1-95e8-5c3e286a7aff/1199_0.7.0.xml#_ac370c9b-7389-4daa-ac5b-338e11dc43e7" id="_ee02dd43-d29c-4a35-83b2-1fc267a0c9fe" referencetype="Text" scope="local" synctargettext="false" type="abcb-glossentry">automatic</xref> fire mode operation, and where applicable, comply with the restart facilities in AS 1668.1; and</li><li id="_1c907718-21de-4a54-b927-fc45e4e1ac2c">must operate at an obscuration level not greater than 0.5% per metre with compensation for external airborne contamination as necessary; and</li><li id="_16fe0efe-fe40-4b8f-b7c3-0a5d478c7537">must sample air within the <xref format="dita" href="/tmp/QppServer/Publishing/5e2c1f63-e589-4ce1-95e8-5c3e286a7aff/1197_1.0.0.xml#_d0042ee6-21cd-4d8c-8873-d8bfb694ceff" id="_7bd322a3-cdf4-4585-96a4-512133aed606" scope="local" type="abcb-glossentry">atrium</xref> and in <xref format="dita" href="/tmp/QppServer/Publishing/5e2c1f63-e589-4ce1-95e8-5c3e286a7aff/1483_25.0.0.xml#_53ff3ea1-55e7-4f2a-b2b3-ca445ff64c15" id="_7709c273-db66-4791-906d-9fb394d79b8f" scope="local" type="abcb-glossentry">storeys</xref> where the bounding wall is set back more than 3.5 m from the <xref format="dita" href="/tmp/QppServer/Publishing/5e2c1f63-e589-4ce1-95e8-5c3e286a7aff/1198_1.0.0.xml#_b070feb5-d14e-4f94-86a5-f7f95371dc36" id="_2c687e89-e2c8-4a8e-9212-7d8b7028d216" scope="local" type="abcb-glossentry">atrium well</xref>; and</li><li id="_ae505500-a9e5-490b-82e2-dd0f32717c90">must be calibrated to compensate for smoke dilution where sampling occurs within return air path common to more than one room; and</li><li id="_8ea99016-421b-4c77-8236-cff3601e8f6b">may incorporate beam type detectors to sense smoke in an <xref format="dita" href="/tmp/QppServer/Publishing/5e2c1f63-e589-4ce1-95e8-5c3e286a7aff/1197_1.0.0.xml#_d0042ee6-21cd-4d8c-8873-d8bfb694ceff" id="_dd9386f8-8146-4c1b-a636-8b98f50e3306" scope="local" type="abcb-glossentry">atrium</xref> in a Class 5, 6, 7 or 8 building with an <xref format="dita" href="/tmp/QppServer/Publishing/5e2c1f63-e589-4ce1-95e8-5c3e286a7aff/1252_2.0.0.xml#_cd986c21-bc64-43a9-954d-86e35d335b74" id="_3e0462eb-e0ca-4278-8db2-f194f779ef63" scope="local" type="abcb-glossentry">effective height</xref> of not more than 25 m if the beam detectors are—<ol><li>located at intervals of not more than 3 <xref format="dita" href="/tmp/QppServer/Publishing/5e2c1f63-e589-4ce1-95e8-5c3e286a7aff/1483_25.0.0.xml#_53ff3ea1-55e7-4f2a-b2b3-ca445ff64c15" id="_11c48012-ab99-416f-8b49-e43c2e357279" scope="local" type="abcb-glossentry">storeys</xref>; and</li><li>arranged to scan at 90 degrees orientation to adjacent beam units.</li></ol></li></ol></subclause></clause>