durationunit 

If present it defines the time unit for the duration attribute. Only codes for integer value time units of the recommended CV (available at http://cv.iptc.org/newscodes/timeunit/ )  must be applied - expressed by a QCode

Attribute Information

Used By

Attribute Group newsContentCharacteristics

Source 

<xs:attribute name="durationunit" type="QCodeType" use="optional">
  <xs:annotation>
    <xs:documentation>If present it defines the time unit for the duration attribute. Only codes for integer value time units of the recommended CV (available at http://cv.iptc.org/newscodes/timeunit/ ) must be applied - expressed by a QCode</xs:documentation>
  </xs:annotation>
</xs:attribute>

Sample