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• Bridge Lighting is Required:
• As prescribed by the Coast Guard District Commander for bridges over navigable waterways
• From sunset to sunrise
• In periods of reduced visibility (less than one mile)
• To be visible for one mile

• Clearance Gauges:
• Should be readable for one-half mile
• Are mainly found on fixed bridges
• Reading at the water level is the clearance from the water to the minimum low steel elevation of the bridge span. (For moveable bridges, the reading shows the clearance when the bridge is in the closed position.)

• Anyone Can, AND SHOULD, Report Discrepancies
• Verifications must be submitted by a Coast Guard certified Aid Verifier

A swing span bridge is mounted on, and pivots horizontally about, its center point. Bridge piers at either end of the moveable bridge span are called DRAW PIERS. The bridge pier in the center on which the moveable span sits and pivots is called the PIVOT PIER.

Swing span bridges may be Double-Opening or Single-Opening. Double-opening swing bridges provide passage on either side of the pivot pier, between the pivot pier and either draw pier. A single-opening swing bridge provides passage only on one side of the pivot pier.

• Each draw pier, or an attached protection pier, is marked by a 180-DEGREE FIXED RED LIGHT on both the Downstream (D/S) and Upstream (U/S) ends of the pier. This light is called a:

  "DRAW PIER LIGHT" or "PIER LIGHT"

  
  
• The pivot pier, or an attached protection pier, is marked by a 180-DEGREE FIXED RED LIGHT on both the D/S and U/S ends of the pier. This light is called a:

  "PIVOT PIER LIGHT"

  
  
• A third pier light, in addition to the two (U/S and D/S) DRAW or PIVOT pier lights described above, may be required if the DRAW or PIVOT piers and the attached protection piers are not straight on their channel faces. This light is a 180-DEGREE FIXED RED LIGHT mounted in the middle of the applicable DRAW or PIVOT pier in line with the bridge axis. This light is called an:

  "AXIS LIGHT"

  
  

• Three light fixtures, each consisting of two red lamps and two green lamps (see diagram below showing the span in a closed position), are located atop the bridge span at either end and at the center point. Each lamp in a fixture is located at 90 degrees from its adjacent lamp and shows through and arc of 60 degrees. When only the green lamps are showing directly upstream and downstream from these fixtures, then the bridge would be in the fully open position. This light fixture is called a:

  "SWING SPAN LIGHT"

  
  

(As Viewed From Upstream)

Note: In order to properly identify any red swing span light discrepancies on an open bridge, it would be necessary to visually determine which direction the bridge closes. However, never request a bridge to close if only to verify bridge lighting.

• Each bascule bridge pier is marked by a 180-DEGREE FIXED RED LIGHT on both the Downstream (D/S) and Upstream (U/S) ends of the pier. This light is called a:

  "DRAW PIER LIGHT" or "PIER LIGHT"

  
  
• When the bridge is in any position other than fully raised, the center of the bridge span is marked by TWO 180-FIXED DEGREE RED LIGHTS (one on the center-most end of each leaf span) on both the Upstream side and on the Downstream side. When fully raised, these lights show 180-DEGREE FIXED GREEN LIGHTS. Each of these lights is called a:

  "RED LEAF SPAN LIGHT" or a "GREEN LEAF SPAN LIGHT"

  
  
• A third pier light, in addition to the two (U/S and D/S) draw pier lights, may be required if the draw piers and attached protection piers are not straight on their channel faces. This light is a 180-DEGREE FIXED RED LIGHT mounted in the middle of the draw pier in line with the bridge axis. This light is called an:

  "AXIS LIGHT"

  
  

(As Viewed From Upstream)

• For facilities that have a GPS /DGPS capability, Aid Verifiers are asked to:
  • Verify LAT/LONG position data that is shown on the Bridge Report Worksheet, or
  • Provide LAT/LONG position data if not shown on the worksheet.


• A bridge location is defined by the extent of the Main Channelwhich may be marked by either a Main Channel Pier Lightor a Main Channel Margin Light. The Bridge Report Worksheet asks for the LAT/LONG coordinates for both:
  • Left Descending Main Channel Pier (or Channel Margin), and
  • Right Descending Main Channel Pier (or Channel Margin)


• LAT/LONG data can be specified two ways:
  • In degrees, minutes, and thousandths of minutes, or
  • In degrees, minutes, seconds and hundredths of seconds (which is the way the data is shown on the Bridge Report Worksheets).


• Always use decimal points when recording the data. Dashes or spaces may be used to separate degrees, minutes and seconds. The following would be valid entries for the same position:

  45 – 81.520

  45  81.520

  45 – 81 – 31.20

  45  81  31.20

  
  

1. For each discrepant light, report the:
   • "As Viewed From" direction -- "U/S" (upstream) or "D/S" (downstream)
   • Position relative to the channel -- "Center", "LD" (left descending), or "RD" (right descending)
   • Lens color -- "Red", "Green", or "White"
   • "CHANNEL" – If Alternate Channel, must specify "Main Channel" or "Alternate Channel"
   • Type / location -- "Pier Light", "Pivot Pier Light", "Span Light", "Axis Light", "Channel Center Light", or "Channel Margin Light"
   • Discrepancy -- "Extinguished", "Dim", "Out of Focus"

     Examples:
             U/S LD RED MAIN CHANNEL PIER LIGHT
             D/S RED PIVOT PIER LIGHT
             U/S GREEN ALTERNATE CHANNEL CENTER LIGHT

2. For extinguished lights, also indicate:
   • If the light fixture is visible
   • If there is a red reflective square or diamond in proximity to where you would expect to find a light.

.
3. Report any damage to bridge protection fenders and cells:
   • Identifying the location as you would a light


4. Report the readability of clearance gauges:

   "READABLE"
   "NOT READABLE" (Specify pier location -- D/S or U/S, LD or RD)
   "NO GAUGES"

The following table shows the light rhythms typical on the inland rivers.

Verification of a light's characteristics is done by timing the light for the number of flashes expected in one minute. Remember: A light's PERIOD is the length of time in seconds during which the characteristics are repeated in regular sequence.

The Number of Flashes Expected in One Minute is Calculated by:

The following table is for light characteristics for Coast Guard aids and private aids commonly found on the inland rivers. The first entry is for the examples used above.

Click on the characteristics in the table below to view a lantern showing the characteristics!

Timing a lighted aid requires a timing device that will give elapsed time. Many wrist watches have this capability but experience has determined that a sports watch (inexpensive, available at K­Mart®, Wal­Mart®, Radio Shack®, etc.) is an easier device to use because of the large buttons and easy-to-read display. And, because it is easier to use, it will tend to give more accurate results. However, the less expensive devices don't have an illuminated display so a flashlight with red lens (to protect night vision) would be needed.

Each Aid Verifier will develop their own techniques for doing the actual timing of flashing lights. The following is suggested as a "starting point" technique for someone who is new to aid verification.

• Always start and stop timing at the end of the last flash in the period. This eliminates the "anticipation" factor that is created when timing repeated sequences.
• Some people are in the habit of counting "one" on the stroke when they start the watch. Of course this throws off the count of the number of flashes. To break this habit, count "zero" when you push the start button on the stopwatch.
• Timing lighted aids must be performed at night. The person doing the timing should be dedicated to that task and should not be interrupted nor should they be expected to be manning any watch positions. Positions should be rotated during the mission.

The following diagrams represent the statements made above:

Note: The following applies to all lights -- on Coast Guard aids, on private aids and on bridges.

In order for a light to be visible as expected, the light must be level so as to show within the viewing range of the mariner. The mounting of dayboards and / or the lantern assembly of a lighted aid is considered to be in focus if they are within plus or minus 15-degrees from the horizontal.

Sometimes it has been observed that the structure (pilings, cells, concrete piers, etc.) is listing as much as 35- to 45-degrees. Often these structures cannot be repaired without totally rebuilding the aid. However, the tower mountings and leveling plate for the light assembly do allow the horizontal position of the aid (light, dayboards, mile board, ...) to be adjusted so as to be in focus (e.g., within the +/- 15-degree tolerance). In this case, as long as the aid can be seen within the viewing range of the mariner, it would be considered as "Watching Properly" assuming that all the other characteristics are operationally correct.

If the aid (light, dayboard, etc.) is not in focus, then specifics regarding the problem should be noted. The structure may show signs of damage. Problems with bridge lighting have been observed because the light fixture was installed facing the wrong direction.

Flashing lights are considered to be "watching properly" when the actual (timed) number of seconds for the expected number of flashes falls within plus or minus three seconds (57.0- to 63.0-seconds inclusive). Example:

If a light with published characteristics of Fl (2) R 6s actually showed twenty flashes in 58.4-seconds, the light would be considered as "watching properly" AS FAR AS THE TIMING CHARACTERISTICS ARE CONCERNED.

Referring to the example above, the Aid Verifier should enter the timing results on the aid verification worksheet as:

"  20   flashes in   58.4   seconds"

Many private aid facilities have more than one light. Unless ALL lights are "Extinguished", the Aid Verifier must identify the specific light for each of the timing results. The table below shows some conventional ways of doing this. It may also be easier to habitually always list the lights starting with most upstream light.

If the location of the lights is identified by ATONIS in the "Remarks" Section of the worksheet, you might be able to list the lights by number starting with the MOST U/S light as #1, then #2, etc.

As an example, for a private aid appearing in the Light List as:

Examples of entries might include:

For the most upstream light:
"MOST U/S = 10 FLASHES IN 59.4 SECONDS" or
"#1 = 10 FLASHES IN 59.4 SECONDS"
Followed by:
"U/S = 10 FLASHES IN 61.3 SECONDS" or
"#2 = 10 FLASHES IN 61.3 SECONDS"
Then:
"Middle = 10 FLASHES IN 56.4 SECONDS" or
"#3 = 10 FLASHES IN 56.4 SECONDS"
And:
"D/S = EXTINGUISHED" or
"#4 = EXTINGUISHED"
Finally:
"MOST D/S = 10 FLASHES IN 60.1 SECONDS, LAMP DIM, LENS CRACKED" or
"#5 = 10 FLASHES IN 60.1 SECONDS, LAMP DIM, LENS CRACKED"

 

Which of the above sample entries would be considered as "watching properly"?

Answer: #1 and #2

 

Referring to the preprinted Class I Private Aid Annual Night Verification Forms published in the Aid Verifier Website:

• The date and time entries recorded at the top of the form are always the actual date and time of the visit. If both daylight and night visits are made, both times may be recorded separated by a slash ("/").

 
• If any timings are outside the tolerance (57.0- to 63.0-seconds, for example), circle "N" after the entry

  Timing of Lamp(s) Correct? Y / N ______________________
  Otherwise, if correct, circle the "Y"

• If a light is extinguished, check " Lamp: (   ) Extinguished " on the form and indicate if a fixture is visible

  If a light is good, check: " Lamp: (   ) Good " on the form.

• If the verification of an aid shows that there are no discrepancies, then check:

  " (   ) WATCHING PROPERLY " under "Remarks" at the bottom of the form.

• If any discrepancies, such as extinguished lights, are considered critical they should be reported via VHF marine radio to the AOR Group. Urgent discrepancies should be reported via phone to the Group or the AOR cutter. Record the fact on the worksheet that such communication was made:

• • 
    

  • 
    

  • 
    

  • 
    

  Critical/Urgent Disc. Reported Via: (   ) VHF Radio (   ) Phone To:               at       Hours on     /     /    

• The Aid Verifier (and only the Aid Verifier) should print their name and member number and sign the report form.

Remember that the people receiving your Bridge and PATON reports are expected to follow up by contacting the owner of the private aid or bridge and get the discrepancies corrected.

As you describe the discrepancy and identify which light you are referring to, make sure the information is accurate and complete. (Some Aid Verifiers even attach pictures!)

Consideration should be given to the poor soul who is thousands of miles from the aid in question and has to deal with the owner over the telephone! Put yourself in their place when you review your work.