A laboratory system has been constructed that uniformly deposits dry partic
les onto any type of test surface. Devised as a quality assurance tool for
the purpose of evaluating surface sampling methods for lead, it also may be
used to generate test surfaces for any contaminant that uses particles or
dust as a transport mechanism. Additionally, it may be used to spike surfac
es for studies concerning particle transport, resuspension, reentrainment,
and exposure. The electromechanical system includes a rugged aluminum chamb
er housing deposition equipment, a computer-controlled positioning system,
and a 0.61 x 0.61 m target surface area (2 x 2 ft). Media used to evaluate
the system have included glass beads of various size fractions (physical di
ameters between 30 and 500 mum), and Arizona Test Dust (aerodynamic diamete
rs between 1 and 80 mum). Presieved particle size fractions may be used ind
ividually to study the effects of monodisperse particles, or may be mixed t
o create custom polydisperse size distributions, Using arrays of 16 coupons
placed on the surface to collect representative samples from every test, t
he uniformity of the particle deposition can be quantified. The system achi
eved an average coefficient of variation of less than 20% for the 16 coupon
s for the particle types and sizes mentioned above and for a variety of tot
al surface loadings (0.3-19 g/m(2)). Calculations of the system's repeatabi
lity (as the average coefficient of variation of mass gains for individual
coupon locations compared across multiple identically configured runs) yiel
ded approximately 10 +/- 5% (one standard deviation). Tests of the system's
accuracy, defined as the absolute percentage difference between predicted
surface loadings and actual loadings, yielded 3.7 +/- 1.3% (one standard de
viation).