Jones also notes that because most of the flash points of the PG grade liquids are lowered, there is less smell to bother neighbors.
"Even if you're only dropping the temperature of a mix by 20 degrees, you're still making an impact," he says. "It's still 20 degrees, and you'll still see benefits of that temperature drop."
Another benefit of supplying WMA is the lower temperatures allow you to increase the recycled materials (RAP) percentage in your mix. On average, says Jones, the Ohio Department of Transportation (ODOT) and the Indiana Department of Transportation (InDOT) allow up to 40% RAP in a warm mix with no blue smoke.
"The WMA gives a good film coat to the aggregate," says Jones. "There's less segregation and better bonds, so ODOT and InDOT allow us to have a higher RAP percentage in the warm mixes."
The lower temperatures while producing warm mix is easier on the equipment, says Jones. "We've used polymers and latex mixes before and you have to get the temperatures up – to 320 degrees for polymers and to 340 degrees for latex – in order for them to work right. That can be hard on the equipment. With WMA, the exhaust temperatures are down, and I've found it's better for the production equipment."
Jones notes that the high cost of oil a few years ago didn't factor into the company's decision to start outfitting its plants with WMA capabilities.
"Yes, you're saving energy and burning less oil," he says. "But, really, the reason to start switching is that this is the future. The positive of WMA far outweighs the negative. I feel warm mix will be mandated from the federal government back to the states in the next four or five years. That's the way it's going to be, so you might as well get used to it."