Laserlux retroreflectometer is a fancy name, but the job it does is simple. It is an instrument that measures pavement markings’ retroreflectivity to ensure the markings are visible to nighttime drivers.

In July, MoDOT purchased its first laserlux device to accomplish that task. The equipment, which is mounted to the outside of the vehicle scans the markings with a laser beam and measures how much light is returned. This device can effectively measure the retroreflectivity even when traveling at normal speeds.

Visible pavement markings are key in keeping drivers safe on Missouri’s roadways. To ensure these markings are visible to drivers, MoDOT must regularly monitor the markings' retroreflectivity.

In the past, MoDOT hired an outside vendor to measure these pavement markings. These readings were costly and the vendor didn’t measure all the pavement markings, just the ones installed by contract and at certain locations.

“The benefits of having our own laserlux will be the flexibility to take readings on a larger scale than we’ve done in the past, while reducing costs,” said Jim Brocksmith, MoDOT technical support engineer. “We have already hired someone to take the readings and purchased a van for the laserlux.”

MoDOT plans to start testing the unit at the end of the summer, once all the components are together. The measurements will be useful in experimenting with new types of pavement markings, quality assurance and for reporting performance results in MoDOT’s Tracker. 

“We consider this laserlux to be a good investment, because it will allow us to have greater quality control measurements of all of our pavement markings,” said Brocksmith. “Greater quality control means safer roads.”