Glove Boxes
Glove boxes
allow the user to perform operations in an atmosphere different for the
ambient. Gloves are built into the
sides or front of a chamber.
Placing hands inside the gloves allows the user to manipulate objects
without breaking the seal or allowing injury to the user.
There are
two types of glove boxes. One type
is designed to allow a person to work with hazardous substances, such as
radioactive materials, highly toxic substances or infectious disease
agents. This type of glove box is
generally maintained at a lower pressure than the surrounding atmosphere. Microscopic leaks would allow air to flow
inward rather than allowing the hazard to flow out.
The other
type of glove box is used for handling air- and/or water-reactive materials
(e.g. organometallics in Chemistry or lithium metal
in Metallurgy). This second type of
glove box is designed to contain a high purity inert atmosphere (e.g. argon or
nitrogen). Inert atmosphere glove
boxes are usually kept at a pressure slightly higher than the surrounding air,
so that any small leaks would be inert gas leaking outward instead of air
leaking inward.
Other
considerations
Training – Any person using a glove box must have been adequately trained.
Flammable materials – A hazard evaluation should be performed before
flammable materials are used in a glove box. These materials should be avoided or
kept at minimum practical amounts.
Type of glove box – Glove boxes under pressure are not intended for use
with hazardous materials. Such
boxes must be clearly identified and controlled administratively to avoid
misuse.
Appurtenances - Glove boxes for hazardous materials often use HEPA
filters in the exhaust to capture materials in use. Some boxes employ equipment (filters,
drying agents) which purify gases introduced into the box.
Gloves – Most glove box failures occur at the glove ports. The ports are capped when not in
use. The flexing of the gloves,
deterioration from corrosives, exposure to UV light gradually reduce glove life.
A well planned inspection and replacement schedule should be followed.
Vacuum gauges – These gauges indicate the negative pressure inside
a glove box used for handling hazardous materials. Before use of a box, the gauge should be
checked to ensure that the box is in safe operating condition.
Ports – Material is introduced or removed through airtight ports. Ports may be small doored
air locks or larger bag covered ports.
These must be designed to prevent loss of negative pressure inside the
main box while the port is in use.
Ports shall be kept free of contamination.
Additional information or questions – Contact the PI in charge or
contact EHS.