Attenuating circumstances: It’s time to pay attention to attenuators

Is there such a thing as TMI about TMAs? TMAs (truck-mounted attenuators) are also called crash cushions, but there’s nothing cushy about them when it comes to keeping drivers and workers safe. 

All kidding aside, we’re serious about your safety and that of workers during the state’s largest urban freeway reconstruction project, the Interstate 10 Broadway Curve Improvement Project. 

Attenuators, whether truck-mounted or fixed, are hard to miss (hint: the yellow and black stripes usually give them away) and you’ve probably seen them along the project area, which spans I-10 for 11 miles in both directions from the Loop 202 (Santan/South Mountain freeways) to Interstate 17. Additional work is occurring on one mile of eastbound and westbound US 60 between I-10 and Hardy Drive and on 1 mile of northbound and southbound State Route 143 between I-10 and the Salt River. 

The mobile TMAs act as a safety barrier between the workers on the job and freeway traffic. A project crew member parks the TMA behind the work crew; if a driver veers into the work site, the vehicle will hit the attenuator instead of a heavy truck or a construction worker. 

Fixed attenuators stay in one place in active work zones. They are usually installed near off-ramps or medians and anywhere a temporary barrier wall comes to an end. 

Fixed or mobile attenuators are designed to absorb the impact of a crash, protecting workers and helping to reduce injuries to motorists and damage to their vehicles. But anytime one is hit, people can be seriously injured. Also, the attenuator must be repaired or replaced right away, which is costly and requires additional lane closures and delays for drivers.

Work zones will be shifting throughout the length of the Interstate 10 Broadway Curve Improvement Project, and fixed attenuators will be added and removed as needed during construction. Mobile TMAs will follow and protect workers for the next three years. Watch for these as you drive through the project area! 

So please slow down, avoid distractions and give our attenuators your full attention. 

All about attenuators: /adot-blog/all-about-attenuators