Silicosis from glassblowing?
Michael Justice
I visited my brother over Thanksgiving weekend, and mentioned that I'd
taken a glassblowing class a few months ago and was about to take another.
He cautioned me against it, saying that glassblowers can develop a lung
problem called silicosis -- the gist of it was that the glass vaporizes,
and when it is breathed in, it solidifies in the alveoli of the lungs,
causing permanent and irreversible damage. His description made it sound
like the furnace just had to hit a "sweet spot" in temperature to trigger
the danger, and that it could happen after a very short exposure if the
conditions were right.
Does anyone know more about this? I'm trying to quantify risk. He's a
radiologist, so although I believe he knows what he's talking about, I
don't think he knows how likely it is or what the conditions would have
to be.
[Note: please email a copy if you post; eskimo.com's newsfeed gets
only about 15% of the articles posted, last time I heard figures.]
Thanks,
-- Michael.
--
Michael A. Justice * lib...@eskimo.com * Member, Libertarian Party
"The House of the Venerable and Inscrutable Colonel was what they called it
when they were speaking Chinese. Venerable because of his goatee, white as
the dogwood blossom, a badge of unimpeachable credibility in Confucian eyes.
Inscrutable because he had gone to his grave without divulging the Secret of
the Eleven Herbs and Spices." -- Neal Stephenson, _The_Diamond_Age_
CRC
silicosis of the lungs is a real concern to all glassblowers. What is
even more hazardous is breating glass particles from cutting. The risk
can be nearly eleminated by using proper ventilation and wearing a face
sheid or mask. I know glass blowers who are still quite athletic after
twenty or more years of blowing glass daily. Taking a class is not
going to be any where near as hazardous (in my opinion) as working with
paint and paint thinners or other chemicals. How about an auto repair
workshop? I have seen mechanics elbow deep in the chemicals used to
clean parts and have seen them breathing high amounts of exhaust fumes.
There are hazards with almost all activities/hobbies/professions a
little caution, preparation, and good sense can make any of these fairly
safe. The biggest problem I have seen with glassblowers are the egos.
In the working environment at least they like to act tough and laugh at
those who protect themselves. This is changing but there is still very
little education about the real risks and prevention. It may be near
the turn of the century but employers are still greedy and do not like
trouble making employees who bring up the subject of health hazards. A
foolish and expensive attitude in the long run.
Chris Canning (making trouble once again) (Hi Roger)
CRC
Tuesday, March 25, 1997
Contact: Frank Kane(OSHA),(202) 219-8151
Contact: Amy Louviere(MSHA),(703) 235-1452
Conference Highlights Partnerships, Approaches For Protecting
Workers From Silicosis
More than 500 industry, labor, government, and health representatives
assembled today to open a
two-day conference in Washington, D.C., to share practical solutions
for preventing silicosis -- a
disabling and sometimes fatal work-related lung disease caused by
overexposure to silica dust.
More than 1 million workers are employed in jobs where they are exposed
to silica exposure, with
100,000 of them at high risk of developing the disease. More than 250
workers die with silicosis
annually.
The conference, which features presentations and discussions on
approaches that are being used
effectively at job sites around the United States, is sponsored by the
Occupational Safety and Health
Administration (OSHA) and the Mine Safety and Health Administration
(MSHA) in the U.S. Department
of Labor, the National Institute for Occupational Safety and Health
(NIOSH) in the U.S. Department of
Health and Human Services, and the American Lung Association.
"When you consider that silicosis was identified 2,000 years ago, our
mission truly becomes more than
just a public policy initiative...or a workplace issue that needs to be
addressed," said Acting Secretary
of Labor Cynthia A. Metzler, the keynote speaker today. "Solving this
problem is nothing short of a
moral imperative."
NIOSH Director Linda Rosenstock, M.D., M.P.H., said, "This national
conference represents a
significant step in the long effort to eradicate silicosis. It provides
a critical link between those who have
already made notable inroads against silicosis in their workplaces, and
others who can learn from those
accomplishments to score similar successes in other mines, construction
sites, and foundries."
During the conference, speakers from business and labor organizations,
companies, agencies, and
occupational health programs will address key practices for effective
worker protection, including
practical engineering controls used in a wide range of workplaces.
Speakers will also address selection
and use of appropriate respiratory protection; educating employers and
workers to recognize and
address potential silicosis risks; and using medical monitoring to
identify employees at potential risk in
time to prevent serious health effects.
Speakers also will discuss current programs that have had proven
success in protecting workers in
construction, mining, and other industries, and the key elements that
make those programs work.
"OSHA is fully committed to this battle to end silicosis," said Gregory
R. Watchman, assistant
secretary of labor for occupational safety and health. "Our national
special emphasis program on
silicosis includes both outreach activities to encourage voluntary
efforts as well as enforcement of
OSHA standards. OSHA has already conducted more than 300 silicosis
inspections."
The Mine Safety and Health Administration (MSHA) is working to educate
the entire mining community
on the silicosis hazard, on mine operators' responsibilities, and on
best practices to prevent the lung
disease, said Davitt McAteer, assistant secretary of labor for mine
safety and health. "This conference
creates a tremendous opportunity to share information on silicosis
prevention from industry to industry,"
McAteer said. "Silicosis has been recognized as a mining hazard for
hundreds of years. The mining
industry has answers to offer others, as well as opportunities to gain
from other industries' experience."
The conference features 20 problem-solving workshops on preventing
silicosis in specific industries and
job operations, plenary sessions with senior government, corporate and
labor officials, and opportunities
to meet with safety and health professionals who have implemented
successful prevention strategies.
"Workers and employers who are concerned about exposure to silica dust
can take preventive
measures to reduce the risk of developing lung disease," said Thomas F.
Gibson, president of the
American Lung Association. "These measures range from the simple act of
quitting smoking to
incorporating inexpensive technology to control silica dust exposure."
Occupations at high risk of silica dust exposure include construction
workers who sandblast or cut,
grind or break concrete, miners, foundry workers, workers who lay and
maintain railroad track and
workers who manufacture glass, ceramics, abrasives or soaps.
Note to editors:
Assistant Secretaries Watchman and McAteer and Dr. Rosenstock, director
of NIOSH, will be available
to news media from 10:30 until noon Tuesday, March 26, in the East Room
at the Mayflower. Another
media availability session for other speakers and workshop leaders will
be held Wednesday from 9:15 to
10 a.m. in the East Room. The conference press room will be in the
CRC
Division of Occupational and Environmental Health
Information Bulletin
June 1989
SILICOSIS AND YOUR HEALTH
WHAT IS SILICOSIS?
Silicosis is an occupational lung disease caused by
breathing in silica dust. Over time this disease can destroy a
person's breathing capacity.
The causative agent is silica, the most common element found
in the earth's crust. It is a major component of beach sand and
granite. Silicosis develops only after long term exposures to
high levels of silica dust.
WHO IS EXPOSED TO SILICA?
In the United States, occupational exposure to silica occurs
in many industries. In particular, individuals in the following
industries and occupations are often exposed.
- Mining, quarrying, loading or transporting of silica
work or sand
- Construction workers involved in highways, tunnels,
cement, plastics, rubber and tile
- Flint workers (breaking, crushing or grinding flint)
- Sand blasting
- Foundry workers
- Workers manufacturing china or earthenware
- Glass industries (unloading, storage and mixing of
silica sand)
There are many other industries and occupations in which an
individual may be exposed to silica.
HOW DOES THE DISEASE DEVELOP?
Breathing in silica dust causes silicosis by damaging an
area of the lungs called the air sac. The presence of silica dust
in the air sac of the lungs causes a body defense reaction that
results in the formation of scar tissue in the lungs. This scar
tissue can limit the ability of the lungs to stretch, thereby
limiting the amount of air that can be breathed in.
It is important to know that you do not have to see silica
dust to breathe it into your lungs. Because the silica dust
particles that are able to reach deep into your lungs and cause
damage are so small, it is impossible to see them.
WHEN DOES THE DISEASE DEVELOP?
Silicosis is normally not apparent until 20 years or more
after the first exposure to silica has occurred. After exposure
to heavy concentrations of silica dust, the development of
silicosis may occur before 20 years. After an exposure to
extremely high concentrations, such as in operations in confined
spaces, a rare acute reaction can occur in 1-3 years.
The rate at which silicosis progresses is related to the
length and level of exposure to silica. The disease may progress
even after exposure has stopped. Therefore, it is extremely
important to prevent excessive exposure to silica dust.
WHAT ARE THE SIGNS AND SYMPTOMS OF SILICOSIS?
At its earliest stage, silicosis can be seen as scarring on
the x-ray without symptoms. As the disease progresses, the
symptoms include frequent dry coughing, shortness of breath,
wheezing and increased tiredness. These symptoms will become
worse in advanced stages until death results from respiratory
failure (lungs are no longer able to function), heart failure,
pneumonia or other complications.
The diagnosis of silicosis is accomplished by obtaining a
complete occupational history, chest x-rays, and lung function
testing. it is very important that workers exposed to silica dust
have chest x-rays at least every 3-5 years. These x-rays should
be evaluated by a qualified medical professional ("B reader")
experienced in reading for silicosis to detect the disease in its
early stages. Lung function tests should be conducted every year
by a qualified technician or physician. These tests will track
any changes in the worker's ability to breathe.
WHAT IS THE MEDICAL TREATMENT FOR SILICOSIS?
There is no known medical treatment to reverse silicosis.
Antibiotics to reduce the severity of lung infections and check
ups for tuberculosis can reduce the complications of silicosis.
However, prevention of exposure is the best method of protection.
WHAT ARE THE COMPLICATING FACTORS OF SILICOSIS?
Tuberculosis
Victims of silicosis are known to be susceptible to
tuberculosis. The reason for this is debated by scientists but it
appears likely that silicosis weakens the defense system of the
lungs to bacterial infection.
Lung Cancer
Although the exact cause is not known, individuals with
silicosis have an increased chance of getting lung cancer.
Heart Attacks
With severe silicosis, in addition to the direct effects on
your lungs, the presence of scar tissue in the lungs also affects
the heart. Your heart must work harder to move blood to all the
areas of your body. This type of strain on the heart increases
the risk of heart failure. Many victims of silicosis will
actually die from heart attacks, rather than silicosis.
Connective Tissue Disease
Rare disorders caused by changes in the immune system may
be increased in individuals with silicosis. Systemic sclerosis is
reported to occur more frequently in individuals with silicosis.
Other Factors/Cigarette Smoking
Cigarette smoking and lung conditions such as asbestosis
can cause an additive crippling effect on your lungs when
combined with silicosis. Because of this, a worker who has an
existing lung disease should never be assigned to an area where
there are high silica exposures. Additionally, a worker with
silicosis should not be placed in an environment or be exposed to
other agents that might cause other damage to the lung.
WHAT CAN BE DONE TO CONTROL SILICA EXPOSURE?
Methods to control silica exposure include:
1 . - Elimination of the toxic material
- Substitution of a less toxic material
- Isolation or enclosure of any dirty operations
- Installation of local exhaust ventilation
- Better maintenance, housekeeping and hygiene
practices
- Changes in work practices to avoid breathing in
silica dust
2. Respirators should be provided and used by the employee
as short term protection when exposure to toxic
materials is suspected.
Respirators, however, should not be used as the only
method of control.
WHAT CAN YOU DO ABOUT SILICOSIS?
If you obtain information that indicates a silica problem
and your employer does not correct the problem, you can contact
two agencies to obtain assistance: the Occupational Safety and
Health Administration (OSHA) or the New Jersey Department of
Health.
OSHA is responsible for enforcement of federal safety and
health regulations, including a regulation requiring employers to
keep silica dust levels below permissible exposure limits. To
find the OSHA office nearest you, contact:
OSHA Region 11 Office
201 Varick Street
Room 670
New York, NY 10014
The New Jersey Department of Health provides consultative
industrial hygiene services to employees and employers about
silica exposure problems. For more information contact:
David Valiante, C.I.H.
Occupational Health Service
New Jersey Department of Health
CN 360
Trenton, NJ 08625
New Jersey State Department of Health
Division of Occupational and Environmental Health
CN 360, Room 706
Trenton NJ 08625-9972
(609) 984-1863
CRC
If anyone has or finds information about the effects of silcon oxyde
that directly relates to the fumes that come from heated glass please
pass it on to me. I will post it on my WEB site for all glass blowers
to read.
Thanks Chris
Chris
As a blower on the floor, I had to wear a device for two working days that
"breathed" the same air as the workers. In all, 10 units were worn. The only
exposure problem was found in the batch room. Too much arsenic was found.
They recommended "no eating, drinking or smoking in the batch room"
(Duh...who would want to eat in the batch room?)
At a lecture at Pilchuck this summer, when asked about silicosis, the
lecturer stated that coal and wood fired furnaces of the first part of this
century has led to more lung problems then anything else. With the
introduction of natural gas, the lung problem of glass blowers has waned.
As a previous posted mention, there is a big worry when you cold work.
Always wear a respirator when cold working. All that water spraying on your
face is full of glass. Even worse is grinding lead crystal. I met a cold
worker who had to be "Ke-lated"(I know I'm not spelling that right. It's
when a person has the heavy metals collected out of his body....not
pleasant), 3 times.
The problem seem to be in the batch, refractories and the dust from ground
glass. As for what takes place during the melt....well so many different
kinds of glasses are melted it would be hard to comment. I think Spruce Pine
gives off allot of vapor from the Antimony (carried off in the steam of
collected moisture) I worked in a shop that had melted Spectrum cullet in
electric furnaces for so many years, the office windows were stained with
Fluorine so badly it was hard to see through them. I've seen 2 tons of
rejected spit bowls (like at the dentist) be melted down (they were white)
and if you got a whiff of the fluorine that was coming out if that furnace
you would be barfing sick (When you gathered and came out of the furnace,
the dip would be "smoking" with fluorine streaming out of it), but they made
cute bunny rabbits.
Nobody has become a glassblower because it was the safest, most
comfortable, easiest job on the block. Most are driven be an inner desire
thats larger then most safety concerns (Not that this is a good thing....I
don't want to bring the whole shop safety thread back to life). That inner
desire in many countries is the desire to feed one's family. Not the self
indulgent luxury item glass blowing that I enjoy the opportunity to
participate in daily.
Chris Steffens
MikeFirth
<< Does anyone know more about this? I'm trying to quantify risk. He's a
radiologist, so although I believe he knows what he's talking about, I
don't think he knows how likely it is or what the conditions would have
to be. >>
silicosis is in the pits. If you read the postings of official documents, you
will see the
only mention of glass is shoveling sand/batch.
There is a real risk of silicosis from working with glass, but it has
nothing to do with
blowing hot glass. It has everything to do with handling batch chemicals and
grinding (cold working) glass. Everyone knows about those and takes reasonable
precautions, which in the case of batch involve wearing a dust mask or
respirator mask during the few minutes at the end of the day when the batch mix
is being shoveled into the furnace. Most grinding must done with water which
carries off the
dust so it is a matter of cleaning up.
There is also apparently a slight risk of a silicosis like disease from the
ceramic
fiber (Fibrefrax being one brand, so Frax for short) that is used by some
people for
insulation. Most of the risk seems to come from working with the stuff
(building)
rather than having the stuff around, but most glass blowers now seal in their
frax with insulating castable refractory or a high temp slurry coating.
Glassblowers as a group (down through history) have never shown signs of
silicosis - heat stress being more a problem - and generally live very long
lives.
As for glass vaporizing, if it did, there would be a thin layer of glass all
over everything in a glass studio and there isn't. Nothing involving
glassblowing gets
anywhere near the temperature of vaporizing glass.
Besides, silicosis is a disease involving the body attempting to deal with
long thin
fibers (of microscopic size) as with asbestos and losing lung capacity as it
encapsilates them rather than washing them out (as it tries with smoke
particles for
example.) Revaporized glass would not form this shape.
Mike Firth, Hot Glass Bits furnace glassblowing newsletter
Mike...@AOL.com Mike...@compuserve.com
Home Page: http://ourworld.compuserve.com/homepages/MikeFirth
Chris
While I agree with most of your post, I have to comment because (at least
on my server) you've posted from my lead on the tread.
> As for glass vaporizing, if it did, there would be a thin layer of glass
all
>over everything in a glass studio and there isn't. Nothing involving
>glassblowing gets
>anywhere near the temperature of vaporizing glass.
Your right, glass does not vaporize. But as the chemicals go into
solution, THEY vaporize ( remember that whole discussion about "what
happened during melting"?). Plus, if you'd do a Dejanews search, you would
find that your Hero, Henry Halem posted this spring about the "vapor point"
of a couple of different colors of glass. I have SEEN HOT GLASS SMOKING!
(That is to say VAPOR billowing off). I have seen a building that had
chemicals built up after years (20 plus) years of batching a glass with a
low vapor point. The windows in the office were stained milky white.
As for glass shops having a thin layer of glass built up; I have helped
rebuild 8 to 10 furnaces, and the 7 electric melts had a thin layer of
"build up" lining the inside walls of the furnace (outside the pot.). I
think this is partly because most furnaces are built DIRECTLY UNDER THE
EVACUATION FAN(!) not because glass doesn't give off vapors.
I tend to acknowledge my antidotal evidence, where as you come forward
claiming absolute knowledge ( I don't mind this except when you're
contradicting me =^} ). As I've said before, publicly , I don't mean to
discount what experience you have, but this time your information is
incomplete.
Chris Steffens
CRC
Visit a quartzshop some time and you will see some serious build up of
silcon oxide.
MikeFirth
In article <366c0...@news.nwlink.com>, "Chris" <gls...@nwlink.com> writes:
Just so frussell and others don't burst a blood vessel, let me say that this
reply has
two parts and the first is just the tinyist bit off topic while the second
smacks of
micromanagement.
1)
> I tend to acknowledge my antidotal evidence, where as you come forward
>claiming absolute knowledge ( I don't mind this except when you're
>contradicting me =^} ). As I've said before, publicly , I don't mean to
>discount what experience you have, but this time your information is
>incomplete.
I am bewildered by your statement "claiming absolute knowledge", just as I
was
bewildered by the assault by frussell when I asked about studio fires and was
accused of almost everything but throwing my first born in the furnace.
Every single word I write is based on my personal (and limited) anecdotal
experience. This is not a scientific forum and I certainly acknowledge that
there
are dozens nay hundreds of people out there with more glassblowing experience
and knowledge than I have. What I have done is visit several dozen glass
studios,
talk to half a hundred or more glass artists, attend a lot of sessions of
three G.A.S. Conferences, gather catalogs from every place I can find offering
glassblowing
classes and tools AND THEN WRITE ABOUT THEM. I believe I own all modern books
on furnace working and have copies of every modern newsletter on the topic. I
did a newsletter on my experiences every couple of months for 9 years.
Anybody else who has more experience (including Henry Halem, who announced he
would and didn't) is welcome to do a newsletter or set up a web
site or ..... I would love it. I would pay to see it. It just ain't being
done.
I am a low experience glassblower who has wandered around, looked and
observed and synthesized what I see. I love what I do with glass. I am ready
to
be corrected on what I say, and I certainly try to say reasonably precisely
without
being pedantic that "most", or "some" or "many" of the glassblowers I have
encountered do thus and so. If I need to install a disclaimer paragraph, I
suppose I shall, to avoid being accused of being absolute.
2) The topic of this thread is named in the subject.
While I will cheerfully accept others experience, I respectfully point out
that
a) while
>. I have seen a building that had
> chemicals built up after years (20 plus) years of batching a glass with a
> low vapor point. The windows in the office were stained milky white.
and while
>> florine fuming off opal glass
and
>> crusts forming inside tanks outside the pot
all indicate that things are happening
and
b) I cheerfully acknowledge there are many chemicals given off in the
glassmaking process which can kill or maim,
HOWEVER :-)
this is not silicosis
and the vapors given off by glass, whatever they are
and however dense they are, are not going to form little
rod like crystals that the lungs have great difficulty dealing
with so damage remains once caused - which is the risk of
silicosis and the reason we wear masks when shoveling
batch and grinding glass and work to keep our space clean
and prevent stuff from floating around in the air.
Chris
> I am bewildered by your statement "claiming absolute knowledge", just as
I
>was
>bewildered by the assault by frussell when I asked about studio fires and
was
>accused of almost everything but throwing my first born in the furnace.
I'll retract my accusation by saying that your answers are (sometimes)
couched in a way that I personally (nobody but me) construe as not allowing
other possibiltites.
But then, as I look at my own past posts, I too have been at fault of this.
> b) I cheerfully acknowledge there are many chemicals given off in the
>glassmaking process which can kill or maim,
To address this piont, I would like to quote from your own text:
"""" As for glass vaporizing, if it did, there would be a thin layer of
glass all
over everything in a glass studio and there isn't. Nothing involving
glassblowing gets
anywhere near the temperature of vaporizing glass.""""
Then I responded with:
"""""
Your right, glass does not vaporize. But as the chemicals go into
solution, THEY vaporize ( remember that whole discussion about "what
happened during melting"?). """""
No one was argueing about sislicosis from molten glass
It was MY FAULT COMPLETELY! From now on, I vow to change the subject line
if the sub-thread starts to wander away from the topic. It was easy to
assume every one was keeping up just as it was easy to assume every one was
talking about silicosis exclusively.
Mike, you bring an interesting slant to many treads. The idea that you are
spending all of your personal time tracking down and reporting information
is inspiring. It shows a love of the process that is hard to deny.
Nobody is attacking you news letter ( The Corning Library
subscribes...that's a good feather)., so lighten up...it's Usenet.
Chris Steffens