Ergonomics and the Design of Glove Boxes

Abstract

Glove boxes, also known as containment cabinets and dry boxes, are being used much more frequently in industrial, university and government laboratories, and in manufacturing processes, as more and more substances are being labelled suspect carcinogens or toxic. Dry boxes are so named because they are designed to protect the substance from the atmosphere. The need to incorporate ergonomics input into the design of glove boxes will be discussed. The published literature concerning ergonomics in glove box design is very sparse. The purpose of this paper is to alert the glove box user to this need, to outline some of the problems encountered in glove box use and to indicate areas where additional studies are needed. The performance of tasks inside a glove box can impose severe constraints, both physical and visual, on the operator. There are physical and visual limitations on reaches and restrictions on the range of arm, hand and finger movements within the glove box. Quite often, awkward body postures and awkward limb movements are required in order to perform the task. Dexterity and manipulative ability are further decreased by the wearing of gloves. These constraints and limitations are very task dependent. The interface between user and glove box most readily lends itself to ergonomics input. Treating the glove box as a special type of individual workplace, existing data and accepted ergonomic principles of workplace design can be utilized in designing this interface. This involves specifying the height of the glove box for either a seated or a standing operation and designing adjustability into this workplace in order to accommodate the individual operator. This ability to adjust oneself to the workplace, and to the task, should minimize awkward body postures and awkward limb movements. This interface and opportunity for adjustment, are the factors most immediately under control of the user organization when setting up a glove box, which is, most often, an off-the-shelf purchase from a glove box manufacturer. Other factors to be considered in designing a glove box workplace are visual constraints, room lighting, gloves (type and size) and pass through provisions (from adjacent glove box or hood). Since the constraints and limitations are very task dependent, ergonomics input is invaluable in specifying or designing special tools, trays and containers that will or can be used inside the glove box. The ergonomist can make recommendations on the placement and positioning of equipment inside the glove box and on the best use of standard laboratory equipment inside the glove box, or, if necessary, suggest modifications to the equipment. This input has to be compatible with the major design considerations involving the complete protection and safety of the user, correct negative pressure, exhaust system, necessary services inside glove box, latch seals, glove attachment, cleaning and decontamination facilties, and other stringent requirements for a completely enclosed system.