Silver Spring, MD: The Center to Protect Workers' Rights, 2007 Jan; :1-29
Field tests of a wet abrasive blasting device resulted in significantly lower respirable crystalline silica dust levels than comparable exposure data reported in the literature. The tested device was the water induction nozzle (WIN) (Boride Products), a venturi nozzle in which water is added to the abrasive-air mixture to suppress dust during abrasive blasting. Workers were monitored for silica exposure while performing abrasive blasting on precast concrete, using the WIN and abrasive sand from which the fines had been removed. The monitoring was conducted at Olympian Precast in Redmond, Washington, over a five-day period in September 2006. The geometric mean respirable dust and respirable crystalline silica exposure levels were, respectively, 0.5 and 0.06 mg/m3. These levels are lower by a factor of 7 (for respirable dust) and 4 (for respirable crystalline silica) than exposure data recently reported for construction workers performing dry abrasive blasting. Controlled laboratory testing is needed to quantify the effectiveness of the WIN nozzle in suppressing dust, separate from the dust control provided by the use of abrasive sand with fines removed. Research is also needed to determine recommended water application rates.
Dust-collection; Dust-collectors; Dust-control; Dust-control-equipment; Construction; Construction-materials; Construction-workers; Control-systems; Exhaust-hoods; Exhaust-systems; Exhaust-ventilation; Air-flow; Laboratory-testing; Filters; Abrasive-blasting; Abrasives; Silica-dusts; Sand-blasters; Sand-blasting; Testing-equipment; Equipment-operators; Equipment-reliability; Construction-equipment; Respirable-dust; Concretes
Building and Construction Trades Department,AFL-CIO, CPWR, Suite 1000, 8484 Georgia Ave., Silver Spring, MD 20910
Construction; Cooperative Agreement
Field Tests of a Water Induction Nozzle as a Dust Control for Abrasive Blasting
Center to Protect Workers' Rights