Proper road tube installation is very important for collecting accurate data with your JAMAR traffic counter.
The following instructions will assist you in placing your road tubes correctly on the roadway.
IMPORTANT SAFETY NOTE: The following instructions should NOT be viewed as a safety guide. Please follow all safety rules and regulations established by your organization and required by your local government. Different localities may have different laws regarding required safety measures for tube count installations. Always maintain compliance to keep yourself, your co-workers, and the general public safe. Suggested safety items include; a highly visible safety vest, work gloves, boots, safety glasses, traffic cones, and a vehicle with safety lights.
Types of Tube
JAMAR currently offers 4 types of road tube; Standard-tube, Mini-tube, D-tube, and the EZ-Belt.
*A JAMAR representative can discuss with you the best tube type for your specific application.
Standard-tube is a circular tube with an inside diameter of .187 inches and an outside diameter of .5625 inches.
Mini-tube is a smaller, lighter version of Standard-tube. Mini-tube is a circular tube with an inside diameter of .187 inches and an outside diameter of .365 inches.
*For most applications, Mini-tube is easier to install compared to Standard-tube. Mini-tube has shown to be effective for up to one million axle hits under normal conditions.
D-tube, also known as Half-round-tube, is a thick, heavy tube typically used for high speed/high volume applications. D-tube has a flat bottom and a round top.
The EZ-Belt is a Mini-tube based system, with a pre-set 4-inch tube spacing.
Preparing Tubes
Preparing and maintaining sets of tubes for your counts will cut down your time near the roadway. Anything that minimizes your time in the field will make your job safer. It will also help you to keep track of how many operational tube sets you have at a given time.
The most common types of traffic counts performed with tubes are: Volume, Speed, and Classification counts.
Volume counts can be performed with 1 tube (the counter divides axle hit pulses by 2). This method is common for collecting ADT counts, but it does not allow for directional information, speed data, or vehicle classification.
Directional Volume, Speed, and Classification counts can all be performed with a set of 2 equal-length tubes. JAMAR’s L-6 tube layout is used to collect this data on 2-lane, bidirectional roadways. For the purposes of covering tube installation, this instruction will focus on the L-6 layout.
*More detailed information on other tube layout types, including the more complex 4 tube setups, can be found in your JAMAR Tube Counter Manual and on our Tube Layouts page.
Tubes will typically come in a 100’ or 120’ single length of coiled hose. The quickest way to prepare a tube set is to unroll the single length of tube, fold it in half, and cut at the fold. Once cut, you will have a set of 50’ tubes for a 100’ roll or a set of 60’ tubes for a 120’ roll.
*Cutting a tube in half is preferred over simply measuring to 50’ or 60’ and cutting. Minor variations in manufacturing and temperature can cause slight deviations from an exact 100’ or 120’ length.
*CRITICAL: Both tubes must be the identical length to each other.
Tube Length and Tube Spacing: Why It Matters
*Two products that can help save time on tube preparation are the EZ-Belt and the Precision Cut Mini-tubes.
Tube Maintenance
As tubes are deployed and exposed to the elements their condition will wear. This will cause slight variations in tube length and durability. Routine tube testing and visual inspections should be performed before taking sets into the field.
*Faulty tubes can produce bad data collection and even cause damage to the traffic counter.
A common test to ensure airtight tubes can be performed by plugging one end of a tube and using a hand pump or bike pump to pump air into the open end. If there are any holes in your tube, the air leak will be apparent.
*The tubes can also be checked after deployment by using the built-in pulse tester on your JAMAR counter (more info below).
PREPARATION
Supplies for a Tube Count Installation
Be sure to have the following supplies so that you can have a successful tube count installation:
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Chains, Locks, and Keys for securing counters (included with purchase of JAMAR counter)
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Road Tubes (Preparing paired sets is recommended, see above for more info)
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Mag Nails [1]
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Clamps, Figure 8 Grips, Chinese Finger Grips, or other accessories for anchoring tubes to road [2]
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Mastic Tape [3]
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Hammer (4lb hammer recommended)
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Measuring Tape
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Utility Knife or Heavy-Duty Scissors
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Crowbar
*It is recommended to have a toolbox stocked with these accessories. It makes for quick prep time, and having your supplies organized will save time in the field.
*JAMAR staff has extensive field experience, so give us a call and we are happy to provide you with additional tips and tricks to help your install go smooth.
[1] JAMAR offers quality, case hardened steel, zinc-plated nails, with a ribbed shank to assure permanent fastening to the road surface. 2 ½” lengths are generally used; use shorter lengths (1 ½” or 2") in cold weather and longer lengths (3 ½”) in hot weather. 4 sizes available.
[2] A variety of clamp and anchor options are available based on personal preference and intended use.
[3] Mastic tape has a rubberized asphalt base with peelable protective paper backing. It is used to secure road tubes to the roadway. The standard (summer) mastic tape is recommended for surface temperatures of 55F and higher. Comes in 60-foot rolls. 4 sizes available.
INSTALLATION
When it comes to collecting accurate data, site choice and installation procedures are just as important as the condition of your equipment.
Site Choice
The ideal installation site will be on a straightaway, have free flowing traffic, have adequate distance from intersecting roads/driveways, and be installed where vehicles are at their typical travel pace (not accelerating or decelerating).
When choosing a site you will also want to have access to a permanent structure in which to secure your counter. Common fixtures for this are utility poles, road signs, guardrails, and light posts.
*Follow all local rules and regulations when determining where to secure your traffic counter.
*It is always recommended to label your counters with your contact information in the event you need to be contacted about the equipment.
Good Location
Bad Location
Installation Procedures
Once you have arrived at your setup location, determine which side of the road you intend to secure your counter. Follow these steps to setup an L-6 tube count:
1. Retrieve the tube set you intend to use for this site.
A tube set should be between 40’ - 60’ in length.
*CRITICAL: Both tubes must be the identical length to each other.
Tube Length and Tube Spacing: Why It Matters
2. Fully unroll the tube set outside the roadway so that you can ensure there are no knots or kinks in the tube.
Unravel any knots if they exist so that your tube can lay flatly on the ground.
One end of this tube set will be connected to the counter (Counter-end) and the other end of this tube set will be plugged and anchored to the roadway (Anchor-end).
3. Always install the Anchor-end of the tubes first.
This will be on the opposite side of the road that you intend to secure the traffic counter. For the purposes of this example, we will assume you are securing your traffic counter on the side of the road that you have parked. This means the anchor-end of the tubes will be installed across the street.
Grasp your two tubes near the end of the set. Monitor for a safe break in traffic. Then cross the roadway while dragging the 2 tubes low to the road surface. Once you cross the street, you should have 2 unsecured tubes lying flat across the roadway.
Plug the anchor-end of the tubes with JAMAR plastic end plugs to block airflow.
Use an end plate or galvanized clamp to anchor your first tube to the roadway. You can do this by slipping the tube through the obvious opening on these items and pin the tube tightly by nailing into the roadway. This will secure the anchor end of the first tube.
Use your measuring tape to measure 2ft from the nail. This is where you will install the anchor-end of your second tube.
Use an end plate or galvanized clamp to anchor your second tube to the roadway. You can do this by slipping the tube through the obvious opening on these items and pin the tube tightly by nailing into the roadway. This will secure the anchor end of the second tube.
4. Monitor for a break in traffic and cross the roadway back to the counter-end of the tubes.
5. It is time to secure the counter-end of the tubes to the roadway.
Have your hammer, nail, and clamp of choice nearby. If you are using Standard-tube, you will need to stretch the tube and hold the tautness with your foot or knee. The tube should be tight enough that it holds its position but not so tight that unnecessary pressure is causing the tube to pull itself from the road. If you are using Mini-tube, you just need to make sure the tube is straight with a light tautness. There is no need to pull or stretch the Mini-tube in any extreme way. With the tube held taut, secure the tube to the roadway by running it through your clamp and nailing the clamp to the roadway.
*CRITICAL: The tube must be perfectly perpendicular to the roadway. A vehicle’s front tires should be hitting the tube straight on, with both front tires hitting the tube at the exact same time.
6. Measure 2ft from the secured tube and repeat step 5 for your second tube.
Now you should have 2 tubes that are installed on the roadway.
*CRITICAL: The tubes must be equally spaced (2ft) apart through the entire roadway. Spot check multiple points between the tubes to verify correct and consistent spacing. The tubes should be perfectly parallel with each other and perfectly perpendicular to the roadway.
7. Now is a good time to identify your “A” tube and your “B” tube.
Keeping track of these is very important for determining which data set belongs to which direction of traffic. Directions will be determined by A to B and B to A.
To determine your A tube, place yourself on the counter side of the road. The lane of traffic closest to you will have vehicles hitting one of your tubes first. The tube they hit first will be your “A” tube. By process of elimination, the other tube will be your “B” tube.
8. Now that you have identified your “A” tube, plug the counter-end of the tube into the “A” port on you counter. Repeat this step for the “B” tube and “B” port.
9. The final installation step is to apply mastic tape.
Mastic tape will help to improve data accuracy by preventing tube rolling and bouncing. It also helps secure your tubes to the roadway. Mastic tape is especially important on high-volume, high-speed roadways.
Cut mastic tape into appropriate strips and apply as needed to secure the tubes.
The tape should prevent tube from rolling and bouncing when a vehicle travels over the tube.
Pro Tip: Take notes of your setup. For example: Direction of travel for A to B, counter serial number, site information, tube layout, GPS coordinates, exact setup time, weather conditions, and anything else that will be helpful.
Programming Your JAMAR Traffic Counter
The final process to completing your installation is setting up your count in your JAMAR counter and checking to make sure it is receiving accurate pulse hits.
Power on your JAMAR counter and select “Count” from the main menu. Then choose “Basic” to get to a list of layouts. Choose the L-6 Layout for this example. You’ll then be prompted to enter a site code of your choosing. After saving the site code information, you will have the option to start the count. It should be noted that the start time on your count file will be set based off the internal date/clock of your counter, so verify that the internal date/clock is accurate. Press “Start” to begin the count.
Once the count has started, you can use the “Tab” button to scroll through a few status screens. There are 2 status screens you’ll want to check before leaving: the axle pulse test and the pulse strength test.
The axle pulse test will display an “A” and a “B,” representing your tubes. As the tubes register axle hits, asterisks will populate the screen. For a standard 2-axle vehicle, you should see 2 asterisks appear after “A” and 2 asterisks appear after “B.” Once you confirm that the counter is accurately registering axle hits, use the “Tab” button to get to the pulse strength test.
The pulse strength test will indicate how well the tube counter is receiving the air pulses from the tubes. As air pulses travel through the A tube and B tube, the counter will indicate how strongly it received the air pulse. If you are getting weak air pulses, check the condition of the tube and verify a correct setup.
Once you’ve confirmed accurate axle hits and strong pulse strength, you are ready to close your counter and secure it to an appropriate fixture. You do NOT need to power down the counter or do anything to turn off the display. Simply close the lid and the display will go to sleep on its own. Chain and lock your traffic counter. Loosely coil up any excess tube and place it near the counter.
Your tube installation is now complete!