Rev. 2001-10-22, 2003-03-30, 2005-02-02, 2006-06-26, -10-29, 2009-01-11

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A WARNING: Working glass is inherently dangerous, involving heavy materials that can be razor sharp, so hot that damage can be done before feeling occurs, with chemicals immediately poisonous, dusts that can damage the lungs, and heat sources that can wreck the eyes. Understand the safe practices required and use them to blow beautiful glass.


First Aid


Eye Protection - Physical

Eye Protection - Optical











FIRST AID - [Burns below]
Getting a piece of glass out can be one of the most difficult removal jobs. It is hard to see and hard to grasp with tweezers and if it is sitting on a nerve can be constantly painful. Unless you are very comfortable folding yourself into a position where you can see the place, not just touch it, you will have to have someone else do the work. If you can do it yourself or get some one, you need a very bright light that can be moved around a bit, like a halogen reading lamp or intense flash light. You will need a strong thin sewing needle (or a scalpel but most people don't have one) and antiseptic like hydrogen peroxide or alcohol. Clean the skin and the tool and use the point of the tool to go in a bit and lift to cut the skin in the area creating a small trench. Use the fingers of the other hand to spread the trench. While working, the person doing the opening needs to listen and feel for the scrape of metal on glass as well as looking for a different texture or gloss. It may hurt to open and to try to move the glass if it is there. If damage has been done, but the glass is out, simply opening the place may take out dirt or other floor stuff pushed into the wound - in which case clean with Hydrogen Peroxide and bandage over.
Many people recommend soaking the wound site in hot water to make access easier.
If the glass is there, it may be difficult and painful to dig under it with the tool or to grip it with tweezers (also sterilized.) If it becomes too painful to work on, clean and bandage the wound and go to a walk in clinic or emergency room or see your doctor and let people work on it.  Sometimes doctors will say the only thing is to let the glass work its way out.  Fortunately, glass does not carry crud that promotes infection.

andrea mcandrews wrote:
Hi, I just started taking a glassblowing class and am interested in pursuing it further, hopefully even to get a job as an apprentice. I was wondering if you know any of the health hazards that go along with working with glass. I was told that the silicon in colored glass is pretty bad for you. Right now though, I am just working in clear, so I was wondering if you could help me out.
Thanks a lot,
Megan McAndrews:)

CHEMICAL RISKS - The silicon in colored glass is irrelevant. The chemicals used to make colored glass or to take the color out of batch are far more dangerous than the silicon. Many glass colors contain lead oxide as it expands the range of coefficients of glass that the color will work. Colors like red or orange are made with cadmium in some cases, a heavy metal poison.

The silicon in glass batch (the sand based powder melted to make glass) is dangerous to the lungs and thus it is advised that a respirator be worn when charging a furnace and an effort be made to avoid scattering the stuff around the studio. Most batch contains antimony oxide, arsenic oxide, or some other chemical to react with chemicals that cause color so the glass is clear or "white" metal and these are far more dangerous, short term, than silicosis.

When glass is ground to change its shape or even out a base (cold worked), both the silicon and the heavy metals may be released. Since water is required when cold working glass to keep it from heating and cracking, normally the dust is never in the air, but is carried off in the water and collected as sludge in whatever trap method is used.

The plastic shield I use, #4 welders.RISKS - There is some risk assumed from the glare of the furnace (or torch heated glass) since the light intensity exceeds OSHA standards and a number 4 welders shade is suggested for actual exposure at the furnace. On the other hand, most glass workers spend relatively little time at the furnace or glory hole. I use a full face plastic shield, #5, both for the eye comfort and for a cooler face; I have become adept at flipping it up and down. Some other people use flip ups on their glasses or mount a filter as a view panel at the edge of a metal heat shield before the furnace.

Eye Protection
Every glass worker should have several levels of eye protection: at a very minimum, break resistant glasses to save the eyes from glass fragments. Furnace workers, according to tests, should be using at least a #3 and preferably a #4 welders shade to observe the furnace and gloryhole. I do this with a relatively low cost ($25) plastic shield on a Jackson 170-S (not the newer 170SB) head band with Glendale Irex (Blue Diamond) 862 shield stocked in #5. The full face shield is also nice in holding off the heat, but I got the idea from a couple in Michigan who cut off the lower half of the shield so they don't have to raise it to blow. I have become adept at raising/lowering the shield quickly.
Glasses commonly used for lampworking are referred to as didymium glasses. This material specifically blocks the yellow sodium flare that blocks viewing the glass in the flame. It does not, in and of itself, block UV or IR, and must be part of shading or other design factors to produce full protection.
Some workers wear welding clip-ons or use a flat piece of welding glass in a frame at the yoke to look through. According to tests, UV is not a problem, IR is too high and protective choices should be made. Many glassworkers use sunglasses or nothing, for better or worse. If your eyes show signs of drying or pain or after effect images, you should be using more protection than you are.
Cataracts from IR were found to be a problem at the end of the manual glassblowing of bottles (1870-1890's) as people lived longer due to better health so more obscure problems could come to the surface.
It is recommended that glassblowers wear cotton or wool clothing rather than nylon or polyester. Part of the reason is the way that natural fibers hold sweat. But also nylon can melt in the heat and if it sticks to the skin is very painful. It is easy to say that the heat will be avoided, but easier said than done. I have a light lined jacket I wore against the fall chill and I melted a portion of the cuff without damaging my hands - the insulated fabric rose in temperature from the radiated heat of the gloryhole while my blood flow kept my hands cooler. Many glassblowers work in short sleeves and short pants and pull on a cotton sock with the toe cut out to protect the arm when working bigger pieces but this provides minimal protection from a flying piece of hot glass or an errant hot tool.
A recent discussion on one board mentioned the risks to women of non-cotton underwear - mentioning specifically a bra that melted from the heat and left a scar.  Reflective cloth for sleeves and under shirts is now available 2004-04-13
If the building has open ventilation, then insects have to be considered.  The three insects that get the most publicity are mosquitoes for West Nile fever, ticks for Lyme disease, and small spiders for nasty little bites, but problems can also arise from bees or wasps taking up residence.  Mosquitoes may breed in standing water so treating the water should be considered.  Insecticides and repellants judicially used will reduce the risk.  Mud dauber wasps (very thin waists) are harmless, but will clog pipes with mud plugs and I recently found a torch with webs inside it clogging small pathways.  I make wind chimes also and something is dragging grass into the tubes hanging in mid-air, stuffing them full and laying eggs that hatch into what look like tiny grasshoppers. 2006-06-26
Heat is different from burns in that heat is an overall effect on the body, while burns (normally in glasswork) effect a small part of the body. Depending on how a glassworker works, the heat exposure of the body can be very high. When I was blowing glass in mid-summer in the Hill Country of Junction, Texas, it was hot (100°F+) but very dry. I normally sweat to the dripping point in north Texas, but drinking close to a gallon a day, I remained dry down there. In an enclosed studio, the temperature can be well above room temperature and at or over 100F near the furnaces where the worker functions. Good ventilation should be provided, with controlled air flow for both furnace area and working area. There should be a good air supply also and furnace area air should not come from the working area as people may find cold winter air chilling and close down required intake air. One person I met in my early years was unable to blow during the day because of what a prolonged exposure to heat - all day - did to his electrolytes before he was thrown in the hospital.
Continuous heat in a studio can dry out wood structure and damage roof material increasing the risk of fire.  One tar roofed academic studio regularly dripped tar from the combination of summer and furnace heat. 2006-06-26
One of the things that people get concerned about is the mass of white molten glass being carried on the end of the pipe and the number of people on the floor. Yet, in my years of working on the floor and talking with people about burns, I rarely hear of a story of someone burned from that hot glass. I believe part of the reason is that hot glass drips if not kept rotating, so it is watched constantly and thus the handler is ready to move it away. Most of the more serious burns I have heard of (anf experienced) have come from picking a pipe or punty from the wrong end [mistaking the dark heat damaged end for the dark rubber handle] or from rolling a pipe and hitting a leg while sitting working. Mild burns from cooling hot glass on the floor, etc., occur also.
Please understand that most glassblowers experience First Degree burns frequently, either from working large glass or pausing too long at the furnace or glory hole.
First Degree - Reddening of the skin with a continuing burning sensation - heavy sunburn
Second Degree - Small to large blisters - damage to surface of skin.
Third Degree - Blackening/charring/cooking of skin - damage to flesh under skin - shock likely.
It is a good idea to keep standard first aid equipment on hand, including soothing antiseptic sprays designed for mild burns. A serious burn should be plunged/soaked in cold water (not ice) as soon as possible (if the skin is not broken, any water may be ok but clean water is better), to drop the body temperature, then treated medically as needed.  Aloe is frequently mentioned for minor burns and some people keep a plant in the window instead of a tube in the medicine chest.
The ideal glass blowing studio could have everything made of concrete and metal and still be at risk from portable propane bottles, packing materials and cloth decorations and wooden tables and shelves.  There is a risk of fire from constant low level heating of wooden materials and it is common for the temp up near the roof to be up over 150F. An indoor outdoor thermometer measuring up there may be helpful as a warning.  I use one with a 10-12' probe on a wire to show me in a lower hallway the attic temps in my home.  Good ventilation is a safety feature for fire as well as heat prostration.  Metal truss roof beams, sheet metal roofing and fire rated sheet rock on the walls are important.  A glory hole or furnace with a gas supply that does not cut off on air failure can have a flame roaring out the front for many feet, igniting materials including clothing.  Molten glass falling on a wood floor can start a fire as can hot glass or pipes placed in a barrel that holds trash.  A hose to supply water will help with cleanup and attack most fires in glass studios.  It will also chill glass flowing from a broken pot.  Furnaces should be arranged to deal with getting the glass out if the pot breaks.
Natural gas rises, propane sinks in still air. Check all connections with soapy water, not a match. Clear out if gas is smelled, provide ventilation, turn off open flames, and track down the leak. If nothing else works, get the gas company in.  Carbon monoxide from improperly burning flames is about the same density of air; more likely from low flames - water heaters or pipe - than furnaces or glory holes. Also from car exhaust when car inside building. Detector needed and can be placed at any height..
Cold glass has sharp edges. At a minimum, inexpensive leather gloves should be kept on hand. Long cuff padded welding gloves cost under $10, eventually getting stiff if heated a bunch. There are gloves on the market with rubber dots on the surface that help grip glass and keep it from slipping. There are also gloves that have Kevlar or other tough fibers to resist cutting through to the hands. If you are like me, keep band aids handy.


Security here means securing your property as much as possible from theft and vandalism.  This is not meant to be an essay on burglar alarms and high tech video cameras, although those can be useful.  A feature of some alarm systems is the ability to place several phone calls in the event of a problem and people have used these to be warned that a furnace has gone down or that power has failed - obviously such a system must have its own battery and more expensive systems will use a cell phone to call to avoid the burglar who cuts the phone line coming in.

A glass blowing studio's most valuable contents are probably the glass objects, attracting a vandal, and the tools.  But the tools really only have value to a glass blower and the most likely threat is a person familiar with the studio who has been fired.

It is my recommendation that security begin with good artificial lighting and a control system for inside lighting that makes it as uncertain as possible to determine whether someone is in the building or not.  This includes being able to turn on and off bathroom and office lights via a timer.  I like the X-10 system sold by Radio Shack as Plug n'Power and by Fry's and others as X-10.  These units can plug in or replace outlets and light switches and are controlled by signals sent over the power lines, so no additional wiring is needed.  A single control unit can manage up to 16 remotes and while there are timer controls available, I much prefer the unit that connects to a computer for programming (and can be unplugged for use to free up a comm port) since setting and resetting the standalone units I find a hassle.  One caution is that X10 needs a bridge between the two legs of 240 power, since it is plugged in to one leg at a 120 outlet and the connection otherwise takes place at the transformer, which is too far away and returns a weak signal.

Locking up the building should be designed in to construction plans, but it can be implemented later.  I recommend that only one door have an exterior key lock and all the other openings be locked with slide bolts or bars that can only be accessed from the inside.  Thus a single door is used for entrance and final exit and that door is made as tough to get through as possible.  Be aware that a really determined thief can get through anything, given enough time or using enough force.  We have all heard stories of people using a stolen car or truck to smash in the front of a store to make off with jewels, ATM's, computers or cigarettes.  Whether or not a glass studio is likely to attract that kind of effort, a battery powered reciprocating saw with a carbide blade or a portable cutting torch can go through most metal guards and locks and a sledge hammer can put a significant hole in a sheet rock or cinderblock wall, given enough time.  Security lighting can reduce the time available to work unobserved.

The main door to a studio should be as heavy as possible and should open inward to reduce access to the hinge pins and to make prying the door more difficult.  The frame should be solid so that it can not be pried sideways to release the locks.  A solid core door or a steel cased door should be used and unless the door is especially strong, the deadbolt lock should be installed on the inside face of the door, not within the thickness of the door.  There is a style of deadbolt that looks ugly, but actually pins the door to frame.  Do not depend on a snap latch to keep people out.

Windows should have a steel grill on the inside and at least one per room, clearly marked, that can be quickly released in the event of emergency, as you don't want someone to be trapped in a room when a fire or gas leak blocks other exits.  But the grill release must be positioned so that is can not be reached by someone who has broken the glass and is reaching through the grill. [As I learned in college, a lock set in a grilled door with a shield may well be opened with a properly shaped tool passed through the grill and moved from hole to hole around the lock.  The release should be easy to move or lift from inside and hard to work if worked near the window - like a bar hanging down that lifts easily from the bottom end but hard near the pivot.]

Each door will have to be examined for the best way to secure it.  If forced to deal with a pair of doors that open out, a security bar that spans the inside frame and drops down snuggly over four hooks, as used at a hardware store I once encountered, may be needed to keep the doors in place as pins may not.  Garage type sectional doors, while admitting a lot of air, have wide enough gaps that it is often possible to attack the latches or bolts from the outside.  Slide bars that move into holes in the track or added brackets on the side may be needed. 2006-10-29, 2009-01-12 edit

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