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 amongst microbiologists that using sharps within containment equipment would increase the operator’s chance of accidental injury due to losses of dexterity within containment and so respiratory protection equipment is the favoured method of containment for these procedures. Using three methods of manual dexterity testing, the effect of latex gloves, a positive pressure respirator, and four forms of containment equipment, a class II safety cabinet, a class III safety cabinet, a half suit and a flexible film isolator were tested against the performance on these tests using bare hands in 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 to working with bare hands alone. The use of containment systems, especially barrier containment systems such as Class III cabinets and isolators, in the microbiology laboratory significantly reduces dexterity and may increase the chances of accidents occurring within. The use of positive pressure respirators with double gloves also affects dexterity but to a lesser extent. The use of sharps should be minimised within containment equipment. Risk assessment may be required to address the comparative risk of aerosol and needlestick infection with different agents in order to choose the most appropriate containment systems.