The effect of microbiological containment systems on dexterity.

Microbiology laboratories use containment equipment such as safety cabinets and isolators or respiratory protective equipment to protect workers against aerosol infection hazards. There is a perception among microbiologists that the use of containment equipment reduces dexterity to a point where the risks associated with using sharps are increased. Thus, in a situation where it is essential to use sharps, the use of respiratory protection is frequently the favored method of operator protection. Using three methods of manual dexterity testing, the effect of latex gloves, a positive pressure respirator, and three forms of containment equipment, (a Class II safety cabinet, a half suit, and a flexible film isolator) were tested against performance in these tests using bare hands in 10 subjects. The study was extended to additionally assess Class III cabinets using 20 subjects. With the exception of latex gloves, the personal protective equipment and containment equipment all had a statistically significant detrimental effect on manual dexterity compared with working solely with bare hands. The use of containment systems, especially barrier containment systems such as Class III cabinets and isolators, significantly reduces dexterity and may increase the chance of accidents. The use of positive pressure respirators with double gloves also affects dexterity but to a lesser extent. The use of sharps should be minimized within containment equipment. Risk assessment may be required to address the comparative risk of aerosol and needlestick infection with different agents to choose the most appropriate containment systems.