A crash attenuator truck, usually called a TMA or truck-mounted attenuator, is shadow protection for a mobile or short-duration lane closure, and it is rented rather than bought by most contractors. Day rates with a driver commonly run $600 to $1,200; a bare monthly rental of the truck and attenuator sits nearer $2,500 to $5,000. The specification the job demands is what narrows the choice.
What the specification actually asks for
An agency's traffic control plan names a test level, most often TL-3 for higher-speed work, and a minimum ballasted weight for the host truck. The attenuator is only certified in combination with a truck inside a stated weight range, so a unit hung on a truck that is too light or too heavy is not compliant even though it looks identical. Get the certification paperwork with the machine.
With operator or bare rental
Most short jobs take the truck with a driver from a traffic control company, because the driver knows the rolling closure pattern and the vehicle is already ballasted and inspected. A bare rental suits a contractor running a long project with its own qualified drivers and its own insurance. Bare rentals carry mileage limits and a requirement that ballast is verified before each shift.
What sits on the bill besides the day rate
Mobilisation to and from site, standby time when the closure is delayed, and overtime past a set shift length are the three lines that move a TMA invoice. Arrow boards, portable changeable message signs and cones are frequently packaged with it. Damage to the cartridge after an impact is a replacement charge, not a repair, and it is the reason the waiver terms are worth reading.
Where this sits among rental yards
Truck-mounted attenuators are traffic safety kit rather than general plant, so the supply is specialist traffic control firms plus a minority of the 4,123 construction machinery rental establishments the Census Bureau counts nationally. Availability is regional and thin, and paving season empties it. Book against your closure dates rather than expecting a unit to be on the yard next week.
Questions people ask about crash attenuator truck
What does TMA stand for?
Truck-mounted attenuator: an energy-absorbing cartridge mounted on the back of a ballasted truck that is parked or driven upstream of a work area to take an errant vehicle's impact instead of the crew. A trailer-mounted version, sometimes called a TA, does the same job behind a towed frame.
Does a TMA rental come with a driver?
Usually, on short-duration work. Bare rentals exist for contractors with their own qualified operators, but the agency's traffic control plan and the rental company's insurance both have a view on it, so confirm before you plan the shift.
How heavy does the host truck need to be?
Whatever the attenuator's certification says, which is typically a ballasted range in the region of 15,000 to 22,000 pounds for common TL-3 units. Ballast is checked and recorded, because the crash performance depends on it.
What happens if the attenuator is struck?
The unit is taken out of service and the cartridge is replaced, not repaired. Expect the rental agreement to bill the replacement, and expect a report to the agency, because a struck attenuator is a recordable incident on most contracts.