SITE VISITS

NWTE has been on site to climb and inspect over 1,500 guyed and self-supporting (lattice) cellular communications and broadcast towers. NWTE also evaluates other structures used for communications such as water towers, building rooftops, concrete poles, wood/timber poles and steel monopoles.

The purposes of a full tower climb are to assess the condition of the tower and the appurtenances it supports and to obtain accurate structural data to be able to correctly perform a structural analysis. After each site visit, NWTE can provide a detailed field report that includes the observations made, a list of deficiencies and items that require maintenance, and photographs taken from the ground and from the tower.

The checklists provided in the Structural Standard for Antenna Supporting Structures and Antennas (TIA-222-G and TIA-222-H) are used as NWTE performs condition assessments and field mapping.

The main items to be assessed include the following:

• Structure Condition (damaged, loose, or missing structural members; connections; climbing facilities; etc.)
• Finish (paint, galvanizing, etc.)
• Lighting
• Grounding
• Antennas, Feed Lines, and Mounts
• Other Supported Appurtenances
• Insulators
• Concrete Foundations
• Guy Wires
• Guy Anchors
• Tower Alignment

Field mapping of appurtenances includes:

• Antenna Inventory (elevation, orientation, type, dimensions, mount details, feed lines)
• Other Appurtenances (climb ladders, waveguide ladders, platforms, lighting, ice shields, etc.)
• Feed Line Inventory (type, orientation on tower, termination elevation)

Field mapping of structural components includes:

• Configuration of Each Section (section height, face width, panel height, bracing configuration, etc.)
• Structural Member Sizes (if pipe, wall thickness is measured with ultra-sound device)
• Base Type
• Guy Anchor Locations
• Guy Wire Information (elevations, types, sizes)
• Connection Details

Because a communications tower is continuously exposed to the weather, which at times is severe and may cause damage, regular assessment and maintenance is required to ensure the structural stability of the tower and to ensure adequate performance of feed lines and antennas. The TIA-222-G and TIA-222-H standards state that maintenance and condition assessment shall be performed, at a minimum, once every three years for guyed towers and once every five years for self-supporting towers. Towers used for essential communications or those that represent a high hazard in the event of failure (Class III or Risk Category III or IV structures), towers in coastal regions or corrosive environments, or towers subjected to frequent vandalism require more frequent assessment and maintenance. Towers should also be assessed after severe seismic events, wind and/or ice storms.

NWTE’s professional engineers (PE) are experienced tower climbers and have completed training courses in Tower Climber fall protection (meets or exceeds ANSI/ASSE Z490.1-2009 & Z359.2-2007, NATE, OSHA, WCB, OH&S and Labor Code Requirements) and RF Site Safety Awareness.

  Photos From NWTE Site Visits

 

Click here to view a slideshow of radio and TV broadcast towers.	Click here to view a slideshow of cell towers.	Click here to view a slideshow of other sites.
Click here to view a slideshow of deficiencies found during tower climbs.	Click here to view a slideshow of scenic shots.	Click here to view a slideshow of scenic winter shots.