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POTENTIALLY HAZARDOUS METAL POWDERS
The risks concerning powder handling can be roughly divided into two large classes: health hazards and combustion and
explosion risk. Each specific risk requires suitable precautions when handling powder. Furthermore some powders pose a
risk in both classes .
As for health risks, the following metals are known to cause health problems upon prolonged or short term extensive
exposure:
•
CoCr and other cobalt containing alloys
•
Nickel & Nickel alloys
Cobalt and some other metals are known to cause poisoning . Nickel is considered to be allergenic, leading to intolerance
after extensive exposure . Other powders, even when they are considered to be non-hazardous or to pose no health risk,
should still be handled with care . Even biocompatible powders, such as titanium alloys, are harmful after inhalation or
contact with soft tissues, causing irritation of lung tissue and those soft tissues . Furthermore even if no health risks are
attributed to a specific powder as to date, there is no guarantee that none will be discovered in the future.
Concerning fire and explosion hazards, the following powders are known to be combustible:
•
Titanium and Titanium alloys
•
Aluminum and Aluminum alloys
•
Magnesium and Magnesium alloys
•
Pure non-noble metals
Accumulations of combustible powder can ignite due to elevated temperatures, open flames, sparks or electrostatic
discharge. When dispersed finely into the air, they are susceptible to dust explosions. Furthermore fine fractions and
condensates of these materials (as you will find in the process filter), are to be considered extremely flammable.
In addition to combustible powders, some materials can react with moisture, generating heat and/or hydrogen gas . Typical
examples include pure aluminum, magnesium and magnesium alloys . The combination means that these powders form an
immediate fire and explosion risk when exposed to moisture.
The end user is required to review the Safety Data Sheet for each material in your facility . Always assume that any material
is both a health and fire hazard.
REACTIVE METAL POWDER STORAGE
To store reactive metal powders in your facility:
•
Use closed containers . Closed containers will prevent accidental dust generation and contamination .
•
Always use conductive containers or containers lined with conductive material . Containers made from a conductive
materials will help dissipate electrostatic charges .
•
Store containers on a grounded conductive surface .
•
Store separately from other chemicals such as, but not limited to, oxidizers and fuels .
•
Store in a fireproof cabinet that is certified for the storage of combustible materials (class 4.1).
•
Make certain you have small containers for small quantities of powder . Do not store small quantities of powder in
large vessels .
•
In the ideal case, large quantities of powders are stored in a suitable separate building, away from the production
environment .
Storage in closed containers will prevent accidental dust generation and contamination, while a conductive material will
help dissipate electrostatic charges .
It is also recommended to store large quantities of combustible powders in fire retarding cabinets or a specifically designed
room. While this will not prevent fire itself, it will prevent powder from igniting immediately by a fire in the vicinity of
the powder storage . This will give your personnel additional time to evacuate and will provide emergency services the
opportunity to extinguish the external fire before the powder stock ignites. In the ideal case, store large quantities of
powders in a suitable separate building, away from the production environment .
You must make certain there is no automatic sprinkler system installed where aluminum, magnesium or magnesium alloys
are stored . These materials will react with water to produce hydrogen which will create an explosion hazard .
3D SYSTEMS, INC.
13
PN:80-D48 REV A
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