Keeping the dust down on museum site…

An industry leader in environmentally responsible demolition and recycling has drastically reduced job site dust in a sensitive urban area by using portable, high-efficiency dust suppression equipment while removing a five-floor concrete, steel and block section of the Fresno (CA) Metropolitan Museum.

Kroeker, Inc. employed a DustBoss DB-60 to cover more than 20,000 square feet with a high-velocity mist of droplets that are atomized to the optimum size for trapping airborne particulates, effectively preventing dust from creating a nuisance or hazard for the heavy vehicle and pedestrian traffic in the heart of downtown Fresno.

“The conventional approach to dust control is to have several laborers manning the hoses and spraying down debris,” commented John Call, Manager of Business Development and Marketing for Kroeker. “That certainly helps, but in this downtown location, we needed something more effective that would not only prevent dust on the ground from kicking up, but would also knock down the particles that did become airborne. Manual spraying just can’t do that,” he said.

The museum demolition was a delicate job, as Kroeker’s mandate was to completely remove the additions built in 1936 and 1951, preserving the original 1920s structure that was once the home of the Fresno Bee newspaper, which will contain the newly renovated museum. To better control the
dust generated by the project, Call and his crews positioned the DB-60 to spray the face of the
building as it came down. With a 25 HP motor that generates 30,000 CFM and a throw of more than 200 feet, the oscillating unit delivers a fine mist of water droplets that are atomized to 50-200 microns, the optimum size for dust particle attraction.

Kroeker employed several excavators for the job, including two 70,000 pound Link Belt 330s and a 150,000 pound Komatsu PC650, as well as hydraulic hammers, universal processors and shears at various pints. The firm also used a 150,000 pound Hitachi PC450 with an 80-foot reach and a UP30 processor at the tip. Engineers mounted an additional water spray and video camera at the tip for additional visibility and control.

“By having water at the top of the project and the mist from the DustBoss draping the front of the structure and ground debris, we were able to provide excellent suppression of airborne particles,” Call observed. Kroeker has long been known for its environmentally responsible approach to demolition and recycling, and the company’s 25-acre facility is able to recycle 95% of all debris it receives into reusable materials. Many of the methods and innovations developed by the firm since it began full-time recycling in 1998 are now in common use by other C&D companies.

To maximize the utility of the DB-60, Kroeker engineers have mounted the versatile unit on a trailer with its own generator, and because all utilities were disconnected for the museum demolition, the company used a dedicated water truck plumbed with a 1-1/2 hose to supply the device. The result is a completely self-contained dust control technique that is easily portable from one job site to another, so it can be transported wherever it’s needed most on any given day.

The DB-60 also incorporates a 10 HP booster pump for increasing water pressure by as much as
150 psi. Further, DCT offers an optional dosing pump that can be used to automatically meter in odor control additives or surfactants for superior particle capture. The unit can be outfitted for potable or non-potable water sources.

“The DustBoss did a great job for us on this project,” Call concluded. “It gave us a powerful tool for trapping and containing the inevitable dust from demolishing this structure and hauling away the debris.” He added that although no formal measurements have been taken, he expects the continued use of the DB-60 will have another positive effect, helping to reduce the amount of dust drawn into equipment air filters.