Protect Your Health with Proper Studio Ventilation by Charles Lewton-Brain

QUESTIONS TO ASK YOURSELF ABOUT VENTILATION IN YOUR SSHOP

Have you minimized all activities requiring ventilation? Can you substitute materials or processes to eliminate some ventilation needs? Is local ventilation (suction of air directly from the work spot) adequate in your shop? Have you considered makeup air and where it is coming from? Has your ventilation system been approved and checked by a ventilation technician? Do you test and maintain your ventilation system regularly?

Ventilation means removing noxious materials, dusts and fumes from the air. It is about preventing you from breathing in chemicals and particles that can damage your lungs.

A good friend of mine died recently from pulmonary fibrosis, caused by his exposure to coal dust and chemical fumes from his materials. Having the proper studio ventilation for your type of work is crucial to ensuring your long-term health.

Avoid the need for ventilation if possible
The best option is to try to avoid the need for ventilation in the first place. If you can substitute a material or process and get similar results without generating dangerous dusts or fumes, consider switching.

Local ventilation
If there is no way for you to avoid the use of ventilation, because you etch, use chemicals, make dusts or mists, or get fumes rising as you work or change materials, having the right ventilation is important.

The best solution is to eliminate the hazardous materials you produce directly from the spot where they are generated. This means applying a suctioning device, slot or tube close to the work area that is generating the dust, mist or fumes that need to be vented. This is called local ventilation. The closer you are to a hood opening, the more effective it is. In general, fumes and dusts being generated should be as close as six to eight inches to the opening of a local suction system. Some writers, like Jeanne Stellman and Susan Daum, even suggest, "Wherever possible, ventilated processes should be totally enclosed."

It is, however, important that vented air is removed completely and is not immediately sucked back into your building by a wrongly placed air-makeup intake duct.

You can purchase and install a single slot/hood for a few hundred dollars, but you should have it checked out by a ventilation engineer.

Having proper studio ventilation is crucial to ensuring your long-term health.

Dilution ventilation is not enough
Dilution ventilation (opening a window next to you, and another one elsewhere, so that air passes you on its way out) is used in many shops. Dilution ventilation is generally not an effective approach. Even materials like rubber cement and some permanent markers demand adequate ventilation over and above dilution.

The book, "Ventilation: A Practical Guide for Artists, Craftspeople, and Others in the Arts," by Clark, Cutter and McGrane, is a good starting point for learning more about the specifics of actually building a ventilation system. There are canopy types, slotted hoods and "elephant trunks." The latter is a hose with a hood that can be moved to different spots on a work surface. Make sure you don't move it (and noxious materials) past your face before the air is ventilated, as can occur with many overhead hoods. Different air flow speeds are recommended for various activities. These systems are commercially available from safety supply companies, and are described extensively in the books mentioned in the "Sources Cited" box (below).

Ventilation can be complicated; you will need to do some research. There are ventilation engineers and inch-thick books on the subject. It also is a good idea to consult a specialist about your own ventilation system needs.

Fume hoods
A fume hood is a good idea if you use chemical solutions and processes. A fume hood should be positioned near the back of the workshop so that if there is an accident, the exits are not blocked. It should have enough aisle space in front of it that people working and moving about the studio do not interfere with its use or the air movement into it. Fume hoods should be tested every time you use them with a smoke trail or soap bubbles. To test, hold a smoking piece of rope or a cotton rag near the opening. The smoke trail should barrel into the opening from six inches on each side of the hood, and go in a straight line to the vent exit once it is in the hood. It's the same with bubbles. You should test all vent hoods this way.

I had two students who went to the hospital with "metal fume fever" because they did not test an extraction system before using it. Metal fume fever is caused by exposure to metal fumes. Symptoms include nausea, dizziness and more. It does not, however, cause permanent damage.

Air is leaving, but what's coming back in?
Ventilation means that air is being sucked out of your workspace. This air then has to be made up from someplace, perhaps from the rest of your building or from makeup intakes placed careful distances from the ventilation exit point. As James Kornberg suggests in his book, "The Workplace Walk-Through," "It is important to ensure that your makeup air is not bringing in vehicle exhaust fumes, is not downwind from a chimney that is putting out toxic fumes, and is otherwise not bringing in noxious air. Talk to a ventilation/furnace expert, or your local fire department about such negative pressure effects. Make sure that you don't create negative pressure in a basement workshop by venting so much air out that it causes air to be sucked into the space through a water heater or furnace exhaust vent -- this back flow can fill your workspace with poisonous carbon monoxide gas.

SOURCES CITED

James Kornberg. "The Workplace Walk-Through." Boca Raton, FL: Lewis Publishers, 1992. Michael McCann. "Health Hazards Manual for Artists." 4th rev. ed. New York: Lyons and Burford, 1994. Jeanne M. Stellman and Susan M. Daum. "Work is Dangerous to Your Health." New York: Vintage-Random House, 1973.

Controlling heating and cooling with ventilation
Venting air can cause heating and cooling problems for the workshop. In general, the most effective way to deal with proper ventilation and still consider the cost of heating the workspace is to reduce the amount of air being handled, and to use it only when it is necessary for a specific task. For local ventilation, a low-volume but high-air-speed hood, sort of like the slit of a vacuum hose, can be very effective.

Do I still need a respirator?
Remember that respirators should be reserved for emergency procedures. As Michael McCann writes in his book, "Health Hazards Manual for Artists," "Ventilation should always be tried before considering respiratory protection." If you need to use a respirator, your ventilation system is probably inadequate for your task.

As with any studio equipment, cost is often a good representation of quality. There are many ventilation products available for many different uses. It's imperative to do some research before you buy. Consult books on the subject and the experts who write them, and buy the best system you can afford.

Charles Lewton-Brain is a widely recognized goldsmith and author. He invented Fold-forming, a new system of working sheet metals. His just published book, "The Jewelry Workshop Safety Report," is available from: Brain Press, Box 1624, Ste. M, Calgary, Alberta, Canada T2P 2L7; (403) 263-3955; fax: (403) 283-9053; e-mail: brainnet@cadvision.com.

MAY 2000: TABLE OF CONTENTS