SILICOSIS IN
SANDBLASTERS
USE SILICA SUBSTITUTES
Division of Epidemiology, Environmental and Occupational Health
Services
Something is still killing sandblasters. It is a lung disease called silicosis, and it
is preventable. The disease and its cause have been recognized for decades; yet many
sandblasters still contract this debilitating and deadly disease caused by the inhalation
of silica sand dust.
Because controlling a sandblaster's exposure to silica dust is apparently so difficult,
one way of reducing the risk of silicosis to this segment of the work population is by
substituting a less toxic material for silica sand during abrasive blasting operations.
Great Britain and the European Economic Community have restricted the use of silica
sand as an abrasive blasting material since 1949, and 1966, respectively. The National
Institute of Occupational Safety and Health (NIOSH) has recommended since 1974 that silica
sand (or other substances containing more than one percent free silica) be prohibited as
an abrasive blasting material and that less hazardous substitutes be used.
There are a number of materials available as alternative abrasive blasting media. The
major substitute materials are listed inside this bulletin along with some information
about each. Additional information regarding particular applications should be obtained
from the distributors of the various substitute material.
Note that the cost per ton is misleading when compared to silica sand because many of
the listed substitutes are recyclable and can therefore be reused. A more useful index of
actual cost is price per square foot. A formula used in the industry to calculate the cost
per square foot is presented on the last page of this bulletin. The real cost will vary
depending on the particular application and factors associated with each job. When
compared to silica sand in this manner, you will find that the costs of some silica
substitutes are competitive.
The health effects of many of the silica substitutes have not been determined, and the
materials removed by abrasive blasting are often very hazardous. It is therefore important
to remember that no matter what abrasive blasting material you use, you must still employ
appropriate control measures (e.g. containment, ventilation, and filtration) as well as
provide workers with training and effective personal protective equipment (e.g.
respirators and clothing).
New Jersey State Deparment of Health
Occupational Health Service
Surveillance Program
CN 360, Trenton, N.J. 08625-0360
(609) 984-1863
Silica
Substitutes
|
PRICE* |
SPECIAL EQUIPMENT |
PROPERTIES |
ALUMINUM OXIDE |
$660/Ton |
None Required
(Usually Used in Cabinets
or Rooms with Recycling Equipment |
Closely Sized
Very Hard (MOH 8.5-9) |
BAKING SODA
(Sodium Bicarbonate) |
$900/Ton |
Yes
(Meters Less Product/Min
and Dries Air) |
Natural (FLow and Rinse Agents
Added)
Water Soluble
Non-Sparking
Non-Flammable |
COAL SLAG |
$44/Ton |
None Required |
Hard (MOH 6-7)
Angular
Uniform Density
Low Friability |
COPPER SLAG |
$50/Ton |
None Required |
Hard (MOH 7-8)
Blocky
Sharp Edged |
CORN COB GRANULES |
$350/Ton |
Special Ventilation
May Be Required in
Enclosed Areas to
Control Combustion |
Medium Hardness (MOH 4.5)
Non-Sparking |
DRY ICE
(Cabron Dioxide) |
$60-80/Ton |
Dry Air Required |
Natural Gas in Solid State |
GARNET |
$325/Ton |
None Required
(Usually Used in
Blast Cabinets
with Recycling Equipment) |
Very Hard (MOH 8)
Very Heavy (S.G. 4.1)
Subangular |
GLASS BEADS |
$500/Ton |
None Required
(Usually Used in
Blast Cabinets
with Recycling Equipment) |
Manufactured of Soda Lime Glass |
NICKEL SLAG |
$70/Ton |
None Required |
Very Hard (MOH 7-8)
Blocky
Sharp Edged |
NUT SHELLS |
$360/Ton |
Special Ventilation May Be
Required in Enclosed Areas to Control Combustion |
Soft
Non-Sparking |
OLIVINE |
$76/Ton |
None Required |
Natural Mineral
Hard (MOH 6.5-7)
High Specific Gravity, Angular |
PLASTIC MEDIA |
$3000-4000/Ton |
None Required
(Additional Components
Required in Order to
Recycle Media) |
Soft
Non-Abrasive
Polyester, Ures, Melamine Varieties |
STAUROLITE |
$75-140/Ton |
None Required
(Additional Components
Required in Order to
Recycle Media) |
Rounded Grains
Hard (MOH 6.5-7)
Irregular Shape |
STEEL GRIT & SHOT |
$425-475/Ton |
None Required
(Additional Components
Required in Order to
Recycle Media) |
Uniform Size
Uniform Hardness
Can be Manufactured to Various Specifications |
Silica Substitutes continued ...
|
APPLICATIONS |
ADVANTAGES |
ALUMINUM OXIDE |
Cleaning Hard Metals (e.g.
Titamium)
Removing Metal
Etch Glass
Carve Granite |
Recyclable |
BAKING SODA
(Sodium Bicarbonate) |
General Paint Removal
Stripping Aircraft Skins
Cleaning Surfaces in Food Processing Plants
Removing Paint from Glass |
Less Material Used/Less Cleanup
Low Nozzle Pressures (35-90 PSI)
Non-Sparking
Water Soluable |
COAL SLAG |
General Paint, Rust & Scale
Removal from Steel
Paint Removal from Wood
Exposure of Aggregates |
Less Than 1% Free Silica
Inert
Fast Cutting
Creates Anchor Profile |
COPPER SLAG |
General Paint, Rust & Scale
Removal from Steel
Paint Removal from Wood |
Rapid Cutting |
CORN COB GRANULES |
Deburring
Paint & Rust Removal from Wood & Metal |
Low Consumption
Low Dust Levels
Biodegradeable |
DRY ICE
(Cabron Dioxide) |
Cleaning Aircraft Parts
Cleaning Exotic Metals |
No Residue Remains
Minimal Cleanup |
GARNET |
General Paint, Rust & Scale
Removal from Steel |
Lower Nozzle Pressures (60-70
PSI)
Low Dust Levels
Fast Cleaning Rates
Can be Recycled 6-7 Times
Low Free Silica |
GLASS BEADS |
Cleaning & Polishing
Deburring |
Uniform Size and Shape
Recyclable
Provide High Luster Polished Surface |
NICKEL SLAG |
General Paint, Rust & Scale
Removal from Steel |
Rapid Cutting |
NUT SHELLS |
Cleaning Soft Materials (e.g.
Aluminum, Plastic Wood)
Cleaning Surfaces in the Petroleum Industry |
High Removal Speed
Non-Sparking
Low Consumption |
OLIVINE |
Clean Light Mill Scale & Rust
from Steel
2.5 MIL Profile & Finer |
Low Chloride Ion Level
Low Conductivity |
PLASTIC MEDIA |
Cleaning Soft Metals &
Composites
Cleaning Metal Fabric Screens |
Inert
Recyclable
Does Not Damage Metal Surfaces
Low Nozzle Pressures (20-40 PSI) |
STAUROLITE |
Cleaning Corroded, Pitted,
Weathered Steel Creating Anchor Profile on New Steel |
Lack of Imbedment
Good Feathering
Low Dust Levels
Recyclable 3-4 Times |
STEEL GRIT & SHOT |
Paint, Rust & Scale Removal
from Steel Surfaces Preparation of Structural Steel in Centrifugal Wheel Units |
Can be Recycled 100-200 Times
Low Dust Levels
Superior Visibility
Portable Blast Rooms Available
Creates Anchor Profile |
Silica Substitutes continued ...
|
LIMITATIONS |
ALUMINUM OXIDE |
Must be Reclaimed and Refused for
Economy |
BAKING SODA
(Sodium Bicarbonate) |
May Damage Soft Brick |
COAL SLAG |
Tendency to Imbed in Mild Steel
May Contain Toxic Metals |
COPPER SLAG |
Tendency to Imbed in Mild Steel
May Contain Toxic Metals |
CORN COB GRANULES |
Does Not Create and Anchor
Profile |
DRY ICE
(Cabron Dioxide) |
|
GARNET |
|
GLASS BEADS |
Does Not Create an Anchor Profile |
NICKEL SLAG |
Tendency to Imbed in Mild Steel,
Poor Visibility, Might React with Corrosion Inhibitors
Used in Wet Blasting
May Contain Toxic Metals |
NUT SHELLS |
Non-Etching
Potential Fire Hazard |
OLIVINE |
|
PLASTIC MEDIA |
Anchor Profile Limited to Soft
Substrates (e.g. Aluminum and Plastic) |
STAUROLITE |
May Contain Up to 5% Free Silica |
STEEL GRIT & SHOT |
|
* Prices are only NJDOL estimates based on the best information available in
1994.
COST PER SQUARE FOOT
A formula for calculating the cost of abrasive blasting per square foot
for surface area:
|
( |
(A*B)
+ C + D |
) + E = Actual Cost |
X |
WHERE: |
|
|
|
A = |
delivered
cost of abrasive media |
( |
$ |
) |
TON |
B = |
consumption
rate |
( |
TONS |
) |
HOUR |
C = |
labor cost |
( |
$ |
) |
HOUR |
D = |
equipment cost |
( |
$ |
) |
HOUR |
X = |
productivity |
( |
SQUARE FEET |
) |
HOUR |
E = |
miscellaneous
(e.g. disposal costs) |
( |
$ |
) |
SQUARE FOOT |
FOR MORE INFORMATION CONTACT
New Jersey Department of Health
Occupational Health Service
CN 360
Trenton, NJ 08625-0360
(609) 984-1863 |
National Institute for Occupational Safety and Health
4676 Columbia Parkway
Cincinnati, OH 45226
1-800-35-NIOSH |
Funding for this fact sheet was provided in part by the
SENSOR Cooperative Agreement with the National Institute for Occupational Safety and
Health |
New Jersey State Department of Health
Surveillance Program
CN 360
Trenton, New Jersey 08625-0360
|