154
Note: When the connectorized version of PTP 400 Series Bridge is used with external
antennas, the figures from the antenna manufacturer for lateral force should be included to
calculate to total loading on the mounting structure.
12.3 Capabilities of the PTP 400 Series Bridges
The structure and mounting brackets of PTP 400 Series Bridge systems are capable of
withstanding wind speeds up to 150mph (242kph). The installer should ensure that the
structure to which the PTP 400 Series Bridge is fixed to is also capable of withstanding the
prevalent wind speeds and loads.
12.4 Wind Speed Statistics
Installers are recommended to contact the national meteorological office for the country
concerned to identify the likely wind speeds prevalent at the proposed location. This will
enable the installer to estimate the total wind loading on the support structures. Examples of
the sort of statistics that are available are:
USA Reported Fastest Single Wind Velocities for Selected U.S. Cities (Source: National
Weather Service)
City, State Wind Velocity
(mph)
Bismarck, North Dakota 72
Buffalo, New York 91
Chicago, Illinois 87
Hatteras, North Carolina 110
Miami, Florida 132
New York, New York 99
Pensacola, Florida 114
UK Meteorological Office (www.meto.gov.uk), peak wind speed contour maps can be
found as Fig 3a/3b at: http://www.meto.gov.uk/education/historic/1987.html