• Durisol is a facing material that uses a wood filler and cement mixture that is water-permeable, insect-resistant and effective at absorbing noise. According to the manufacturer, Armtec, Durisol material offers thermal insulation, energy absorption, non-combustibility, no-toxicity, outstanding exterior durability, and a high strength-to-weight ratio. It’s been manufactured since 1953.

• The proprietary Sound Fighter LSE Panel is constructed from materials that are water-resistant, rust-proof, noncorrosive, and extremely durable in the harshest outdoor environments, the manufacturer says. Sound Fighter has a high-density, UV- and color-stabilized synthetic shell. Next, premium acoustic absorptive media is inserted to absorb unwanted noise by completely diffusing the sound waves. The LSE Panel also contains an acoustic sound board that eliminates noise from penetrating through it.

‘D-Day’

D-Day is Jan. 1, 2011. The “D” in “D-Day” stands for Diesel, because that’s when the long-awaited Tier 4 clean diesel technology begins to become the standard for off-road construction equipment engines.

Three key elements comprise the cleaner diesel program: cleaner diesel fuel, advanced engine technology and aftertreatment. Now, starting in 2011, this new-generation clean diesel technology known as Tier 4 will begin to be required for the construction industry for off-road engines and equipment.

Tier 4 refers to a generation of federal air emissions standards established by the EPA that apply to new diesel engines used in off-road equipment. Essentially, it requires manufacturers to reduce the levels of particulate matter and oxides of nitrogen (NOx) to a level that is 50- to 96-percent lower than the existing generation of diesel engines, reports the Diesel Technology Forum.

Starting with Tier 4 Interim, Tier 4 emissions requirements will apply to new products only and are not retroactive. Examples of regulated applications include excavators, dozers, wheel loaders, backhoe loaders, road graders, diesel lawn tractors, farm tractors, logging equipment, portable generators, skid-steer loaders and forklifts.

The “tiered” series of emissions regulations, beginning with Tier 0, has been in effect for more than a decade, governing new off-road engines and equipment, according to the Diesel Technology Forum. These levels of standards establish progressively lower allowable emissions of nitrogen oxides and particulate matter.

“The Tier 4 standards provide manufacturers with a flexibility provision and include an interim step – Tier 4 Interim – which requires substantial reduction in PM emissions and flexibility in lowering oxides of nitrogen,” the forum says. “A Tier 4 final step includes additional reductions in NOx and HC emissions.”

New Tier 4 generation engines and equipment will require the use of ultra-low sulfur diesel fuel, which has no more than 15 ppm sulfur, according to the Diesel Technology Forum. This fuel has been used since 2006 in on-highway vehicles.

“Older off-road machines and engines can continue to use the higher sulfur fuels, which will be available in diminishing quantities nationwide until December 2011,” the forum says. “Supplies of the old ‘higher sulfur’ diesel fuel will be diminishing rapidly beyond 2010, but still may be available in some more remote locations and areas of the country.”

What is on the horizon? Now that Tier 4 diesel emissions are near zero, under the Obama administration EPA may set its sights on carbon dioxide emissions, which are thought to advance presumed global warming. Thus, the regulators may be able to continue their career mission: issuing regulations. In the meantime, off-road Tier 4 engines will become a reality in 2011.

For more information, visit the Diesel Technology Forum at www.dieselforum.org or visit the Clean Diesel Fuel Alliance at www.clean-diesel.org.

Future Performance of Raised Markers

The Texas Department of Transportation (TxDOT) is looking to recent research to indicate performance of retro-reflective raised pavement markers in 2011 and beyond, it was reported late this year.

Precast concrete pavement slab is lowered into Utah’s I-15 between Clearfield and Layton.