<?xml version="1.0" encoding="UTF-8" standalone="no"?><?Xpress productLine="ncc-clause" ?><clause id="_194616f7-58c0-4ffb-9525-35462bdca7f4" 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>S31C11</sptc><title id="_5967ce5f-d0c0-4a6c-ab49-710af9c48129">Upward air velocity</title><archive-num>2019: Spec G3.8: 3.5</archive-num><subclause id="_1df1d26d-3800-4000-8290-c2eed8815fa8" outputclass="subclause"><title id="_ef1d28de-7bfa-4049-8665-de180c3b2aaa">SubClause</title><num>1</num><p>Notwithstanding <xref format="dita" href="/tmp/QppServer/Publishing/5e2c1f63-e589-4ce1-95e8-5c3e286a7aff/826_7.3.0.xml#_1db9fe54-3d68-41ef-99b8-ed49d3abdc28" id="_946ab90a-f3e8-4553-96fe-8408d1a50048" scope="local" type="clause">S31C10(c)</xref>, the average upward air velocity in the <xref format="dita" href="/tmp/QppServer/Publishing/5e2c1f63-e589-4ce1-95e8-5c3e286a7aff/1197_1.0.0.xml#_d0042ee6-21cd-4d8c-8873-d8bfb694ceff" id="_9678a28c-350d-4e14-85e9-16f1800b916a" scope="local" type="abcb-glossentry">atrium</xref>, due to the <xref format="dita" href="/tmp/QppServer/Publishing/5e2c1f63-e589-4ce1-95e8-5c3e286a7aff/1432_4.0.0.xml#_af6fde9f-147d-4782-8b85-42044e80fd42" id="_3e128473-bf02-41f9-a3a8-6e2e91f29f63" scope="local" type="abcb-glossentry">required</xref> smoke exhaust quantity must—</p><ol outputclass="alpha"><li id="_c61d817b-294c-49e7-b777-c63d94b53be2">be not less than 0.2 m/s at any level over an 18 m height above the floor of the <xref format="dita" href="/tmp/QppServer/Publishing/5e2c1f63-e589-4ce1-95e8-5c3e286a7aff/1197_1.0.0.xml#_d0042ee6-21cd-4d8c-8873-d8bfb694ceff" id="_1c166d6c-7f6f-4cca-9e97-7991af240ac6" scope="local" type="abcb-glossentry">atrium</xref>; and</li><li id="_91f2c1e8-6309-476c-b31c-376bee4d38ce">not exceed the following maximum velocities in <xref format="dita" href="/tmp/QppServer/Publishing/5e2c1f63-e589-4ce1-95e8-5c3e286a7aff/1197_1.0.0.xml#_d0042ee6-21cd-4d8c-8873-d8bfb694ceff" id="_d38b0545-17e7-4a43-99f5-0d1f3b9dcda1" scope="local" type="abcb-glossentry">atriums</xref> of constant cross sectional plan area:<ol><li>For occupancy classification qualifying for 1.5 MW fire size — 3.5 m/s.</li><li>For occupancy classifications qualifying for 5 MW fire size — 5 m/s.</li></ol></li></ol></subclause></clause>