Production of Air Borne Particles from Nonwoven Fabrics

Abstract

Disposable surgical gowns and drapes made of nonwoven fabrics (NWF) has been used increasingly. Our purposes of this study is quantitative comparison of air borne particles produced by eleven kinds of NWF.We investigated the number of air borne particles from these NWF by particle counters on mechanical vibration and friction according to the methods described. These 11 kinds of NWF were divided to next five groups.Group A : Dry laid nonwoven fabrics (parallel type).Group B_1 : Wet laid nonwoven fabrics-reinforced synthetic fibers.Group B_2 : Wet laid nonwoven fabrics-tissue reinfororced with scrim.Group C : Dry laid nonwoven fabrics with all pulp.Group D : Cotton fabrics.Methods. Vibration test : A corner of 25×25cm square sample of NWF was shaken in 3 cm wide and 570±12 times in a minute by electrical motor. At the point of 30cm far from the sample, air borne particles were measured by a particle counter.Friction test : By using pilling tester, same kinds of two samples which were 4 inch square were rubbed under the pressure of 41.68g/cm^2 and 86 times in a minute. Air borne paticles were measured at the point of 2cm far from the friction points.These studies were performed in a bioclean room.The results revealed that on the vibration test, the order of numbers of particles more than 0.3μm of diameter were D>B_2>C>A>B_1 and on the friction test, the same tendency was gained more cleary.We conclude that all kinds of NWF produce smaller amount of particlude than cotton fabrics and suspect that the differences of the number of particles among NWF depends on the containing ratio of latex and cotton fibers.