Comparison of three tracer gases for determining ventilation effectiveness and capture efficiency

<?xml version="1.0" encoding="UTF-8"?><collection xmlns="http://www.loc.gov/MARC21/slim" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.loc.gov/MARC21/slim http://www.loc.gov/standards/marcxml/schema/MARC21slim.xsd">
  <record>
    <leader>00000nab a2200000 i 4500</leader>
    <controlfield tag="001">MAP20071017881</controlfield>
    <controlfield tag="003">MAP</controlfield>
    <controlfield tag="005">20080418115226.0</controlfield>
    <controlfield tag="007">hzruuu---uuuu</controlfield>
    <controlfield tag="008">940311e19910801gbr||||    | |00010|eng d</controlfield>
    <datafield tag="035" ind1=" " ind2=" ">
      <subfield code="a">6800003375</subfield>
    </datafield>
    <datafield tag="040" ind1=" " ind2=" ">
      <subfield code="a">MAP</subfield>
      <subfield code="b">spa</subfield>
    </datafield>
    <datafield tag="084" ind1=" " ind2=" ">
      <subfield code="a">872</subfield>
    </datafield>
    <datafield tag="245" ind1="1" ind2="0">
      <subfield code="a">Comparison of three tracer gases for determining ventilation effectiveness and capture efficiency</subfield>
      <subfield code="c">R. Niemelä... [et al.]</subfield>
    </datafield>
    <datafield tag="520" ind1=" " ind2=" ">
      <subfield code="a">Sulphur hexafluoride, nitrous oxide and helium were compared as tracer gases for determining the mean residence time in a test room and the capture efficiency of a local exhaust hood. The mixtures of tracer gases were fed into the inlet air and two sites in the test room with and without mixing of room air. It dertermined the capture efficiency by releasing the tracer gases through the cylindrical injection system in front of the exhaust hood at different capture velocities under various cross-draught conditions. The results of the measurements in the test room showed good agreement between the different tracer gases except in the stagnant zone. The first capture efficiency measurements indicated that SF6, the heaviest gas, gave smaller values obviously due to imcomplete mixing of tracer gases. However, the difference disappeared when mixing of the tracer gas was speeded up pumping extra air or by modifying the injection system</subfield>
    </datafield>
    <datafield tag="650" ind1="1" ind2="1">
      <subfield code="0">MAPA20080585679</subfield>
      <subfield code="a">Higiene industrial</subfield>
    </datafield>
    <datafield tag="650" ind1="1" ind2="1">
      <subfield code="0">MAPA20080605278</subfield>
      <subfield code="a">Contaminantes químicos</subfield>
    </datafield>
    <datafield tag="650" ind1="1" ind2="1">
      <subfield code="0">MAPA20080565817</subfield>
      <subfield code="a">Gases tóxicos</subfield>
    </datafield>
    <datafield tag="650" ind1="1" ind2="1">
      <subfield code="0">MAPA20080613655</subfield>
      <subfield code="a">Control de contaminantes</subfield>
    </datafield>
    <datafield tag="650" ind1="1" ind2="1">
      <subfield code="0">MAPA20080616441</subfield>
      <subfield code="a">Contaminación atmosférica</subfield>
    </datafield>
    <datafield tag="650" ind1="1" ind2="1">
      <subfield code="0">MAPA20080538934</subfield>
      <subfield code="a">Helio</subfield>
    </datafield>
    <datafield tag="650" ind1="1" ind2="1">
      <subfield code="0">MAPA20080566753</subfield>
      <subfield code="a">Oxido nitroso</subfield>
    </datafield>
    <datafield tag="650" ind1="1" ind2="1">
      <subfield code="0">MAPA20080606411</subfield>
      <subfield code="a">Hexafluoruro de azufre</subfield>
    </datafield>
    <datafield tag="650" ind1="1" ind2="1">
      <subfield code="0">MAPA20080612597</subfield>
      <subfield code="a">Sistemas de ventilación</subfield>
    </datafield>
    <datafield tag="650" ind1="1" ind2="1">
      <subfield code="0">MAPA20080560997</subfield>
      <subfield code="a">Ventilación</subfield>
    </datafield>
    <datafield tag="700" ind1="1" ind2=" ">
      <subfield code="0">MAPA20080030544</subfield>
      <subfield code="a">Niemelä, R.</subfield>
    </datafield>
    <datafield tag="740" ind1="4" ind2=" ">
      <subfield code="a">The Annals of occupational hygiene</subfield>
    </datafield>
    <datafield tag="773" ind1="0" ind2=" ">
      <subfield code="t">The Annals of occupational hygiene</subfield>
      <subfield code="d">Oxford [etc.]</subfield>
      <subfield code="g">nº 4, August 1991 ; p. 405-417</subfield>
    </datafield>
  </record>
</collection>