The Meteorological Office, the Transport and Road Research Laboratory and the Home Office have combined in a trial to evaluate potential low-cost visibility instruments as possible aids in motorway traffic control. The results of the trial show that the two instruments under test came close to the performance criteria laid down before the trial but that each had limitations. The short-baseline transmissometer showed a temperature drift which was sufficient to give an apparent visibility change of 7 m/degree C (at 200 M), and the forward-scatter instrument gave poor results when obscuration was caused by factors other than fog (for example precipitation or spray).(a) /TRRL/

  • Availability:
  • Corporate Authors:

    Her Majesty Stationary Office

    49 High Holborn
    London WC1V 6HB,   England 
  • Authors:
    • Douglas, H A
    • Jeffery, D J
    • Jezzard, F
  • Publication Date: 1978-8

Media Info

  • Features: Figures; Photos; References; Tables;
  • Pagination: p. 242-249
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00193959
  • Record Type: Publication
  • Source Agency: Transport Research Laboratory
  • Files: ITRD, TRIS
  • Created Date: May 26 1979 12:00AM