<?xml version="1.0" encoding="UTF-8" standalone="no"?><?Xpress productLine="ncc-clause" ?><clause id="_e4699a87-10a6-4028-996d-6734e8dbb1c9" 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>S21C6</sptc><title id="_b118afa2-ed9d-4002-bc08-5a93ba47dd46">Make-up air</title><archive-num>2019: Spec E2.2b: 6</archive-num><subclause id="_f24ba782-b2f9-47b9-aa6f-ab487ae2275d" outputclass="subclause"><title id="_ec80f907-1e2b-4ce1-9081-c3f6d0418088">SubClause</title><num>1</num><p>Low level make-up air must be provided either <xref format="dita" href="/tmp/QppServer/Publishing/5e2c1f63-e589-4ce1-95e8-5c3e286a7aff/1199_0.7.0.xml#_ac370c9b-7389-4daa-ac5b-338e11dc43e7" id="_2022fd2e-ac48-496d-9325-5c4a7f38d7ab" scope="local" type="abcb-glossentry">automatically</xref> or via permanent ventilation openings to replace the air exhausted so as to minimise—</p><ol outputclass="alpha"><li id="_8207498e-99bc-42e0-b437-0ae6afa6e345">any disturbance of the smoke layer due to turbulence created by the incoming air; and</li><li id="_5844b83b-cb8a-4ad9-83cb-e60b8802f3de">the risk of smoke migration to areas remote from the fire due to the effect of make-up air on the air balance of the total system.</li></ol></subclause><subclause id="_aba7b578-d4d1-495c-a15e-b52fe676107c" outputclass="subclause"><title id="_ecdc25b5-ca95-418d-9341-c43267d68c05">SubClause</title><num>2</num><p>The velocity of make-up air through doorways must not exceed 2.5 m/s.</p></subclause><subclause id="_6ec3433f-4d4b-435f-82b3-a0cc65dbc863" outputclass="subclause"><title id="_e65f3563-05f5-4ae4-8e5d-497936727828">SubClause</title><num>3</num><p>Within a multi-<xref format="dita" href="/tmp/QppServer/Publishing/5e2c1f63-e589-4ce1-95e8-5c3e286a7aff/1483_25.0.0.xml#_53ff3ea1-55e7-4f2a-b2b3-ca445ff64c15" id="_7b51c0b5-4887-428a-b307-74e7e84609d6" scope="local" type="abcb-glossentry">storey</xref> <xref format="dita" href="/tmp/QppServer/Publishing/5e2c1f63-e589-4ce1-95e8-5c3e286a7aff/1277_2.0.0.xml#_524b0326-5823-4ddc-9eb3-adab587568e8" id="_8b24dbe0-e2a1-4663-982f-ac25b28ecd3a" scope="local" type="abcb-glossentry">fire compartment</xref>, make-up air must be provided across each vertical opening from a building void to the fire-affected <xref format="dita" href="/tmp/QppServer/Publishing/5e2c1f63-e589-4ce1-95e8-5c3e286a7aff/1483_25.0.0.xml#_53ff3ea1-55e7-4f2a-b2b3-ca445ff64c15" id="_75a4ac35-3150-47bf-aeb7-9b37f7f096aa" scope="local" type="abcb-glossentry">storey</xref> at an average velocity of 1 m/s so as to minimise the spread of smoke from the fire-affected <xref format="dita" href="/tmp/QppServer/Publishing/5e2c1f63-e589-4ce1-95e8-5c3e286a7aff/1483_25.0.0.xml#_53ff3ea1-55e7-4f2a-b2b3-ca445ff64c15" id="_cff8f0b1-248a-40e7-a350-54a16b9f4ad8" scope="local" type="abcb-glossentry">storey</xref> to other <xref format="dita" href="/tmp/QppServer/Publishing/5e2c1f63-e589-4ce1-95e8-5c3e286a7aff/1483_25.0.0.xml#_53ff3ea1-55e7-4f2a-b2b3-ca445ff64c15" id="_6afbc5ff-f850-49e1-83f1-ce75b7fbe223" scope="local" type="abcb-glossentry">storeys</xref>.</p></subclause></clause>