The Complete Guide to Ventialtion & Indoor Air Quality Control

Editor’s Note: The issue of salon ventilation has been the single biggest health concerns for nail technicians for years. Our writer, Victoria Wurdinger, spent months in the research and writing of this piece, and what she has come up with is a very comprehensive guide to ventilation. This article is long and technical, but it contains some of the most important information you need to work safely as a nail technician. Please take the time to read it carefully, and use it to make sure your own salon is up to standard.

Sabre Bridgers remembers well the day she was told to quit her job at Head To Toe Salon in Hilton Head Island, S.C. She had been coughing and sneezing uncontrollably, had developed asthmatic bronchitis, and suffered from chronic colds. Her doctor gave her an ultimatum: Start wearing a dust mask at work or get out of the nail business.

“I remember thinking, ‘This is all I’m trained to do,’“she recalls. “I make good money at this job and couldn’t see myself taking a $5-an- hour job at the bank after 12 years in a business I like. That’s when I started investigating ventilation systems.”

Bridgers decided to get serious about ventilation and scrutinize every available avenue until she found a ventilation system that worked for her. Today, she continues to do nails and says she’s had no problems at work for almost a year.

It took a severe warning before Bridgers realized that an open window isn’t adequate ventilation, but many other nail technicians still believe that it is. However, simply opening the windows doesn’t ensure quality air indoors nor does it adequately minimize the inhalation of pollutants.

While not everyone develops allergies or sensitivity to the chemicals they work with or near, enough nail technicians do to warrant industry concern. Millions of American workers in buildings with mechanical heating, ventilation, and air conditioning (HVAC) systems — including salon workers — are exposed to indoor air pollution because the dust particles, chemicals, and gases that are present aren’t always vented to the outside, which causes indoor air quality to deteriorate.

Compounding the issue, gases come from numerous sources other than chemicals. Today, it’s recognized that everything from photocopying machines to our own breath (we exhale carbon dioxide) produces gases that can have a negative effect on indoor air quality.

Because of the increased aware­ness of indoor air quality, ventilation has become one of the most important worker health issues today, es­pecially among nail technicians, and one of the most misunderstood.

THE PROBLEM WITH VENTILATION

While heating and air conditioning are straightforward operations, ventilation is much more complex and much more vital. Each state in the country defines “well-ventilated” differently, and that definition refers only to the exhaust of carbon dioxide, not chemicals or particles. Additionally, ventilation standards vary among different industries. Many of these standards were created to regulate building design, not building operation and, most troubling of all, it’s almost impossible to be certain that your building or work area is completely safe unless you’re an engineer or industrial hygienist and even then there is no absolute certainty.

Ventilation poses special problems for nail technicians, who are exposed to filing particles and use solvents, polymers, monomers, and acrylates on a daily basis. While working in a nail salon is hardly the same as working in a chemical plant, any industry that uses chemi­cals must make good ventilation a primary concern. You must have a system that keeps the level of chemicals in the air as low as possible by exhausting them outside, bringing in fresh air, and using spot ventilation where pollutants originate.

Vapors that are unseen and odorless are particularly insidious because less-regulated industries, like the nail industry, tend to forget about them. It’s ironic that highly regulated industries have fewer problems with overexposure to toxic vapors because safety precautions are mandatory for them.

HVAC systems

To understand the issues involved in nail salon ventilation and the specific systems available, you need to understand HVAC systems. According to the Environmental Protection Agency (EPA), ventilation is a combination of processes which results in both supply to and removal of air from inside a building. Outdoor air is brought in and mixed with indoor air, then mixed throughout the building, then some portion is removed from the building as exhaust. If any one of these processes is inadequate, the quality of indoor air can deteriorate.

There are many things that can interfere with these processes: outdated or poorly maintained HVAC systems, employees working too close to exhaust and intake vents, the presence of chemicals or vapors, hindrances to airflow, and, in modern buildings, insulation and windows that don’t open.

Controlling pollutants at the source is the most effective way of maintaining breathable air; ventilation is the second most effective way. Industrial hygienists recommend both primary and secondary, or “spot,” ventilation in any building where chemical vapors gather.

VENTILATION STANDARDS

Ventilation standards for minimum indoor air quality in buildings are set by the American Society of Heating, Refrigeration and Air Conditioning Engineers (ASHRAE) under Standard 62-1989. These standards specify the rate at which outdoor air is brought in and are based primarily on the need to control odors and carbon dioxide levels. Since these standards are voluntary, they are only enforceable after a state or municipality adopts them in the building code. Then, they apply only to building design, not building operation. However, even if a state has adopted these standards there will probably always be building owners who cut corners in order to save money on energy costs.

Minimum ventilation standards are expressed in units of cubic feet per minute, per person (cfm/per- son). According to Nellie Brown, a biologist and chemist specializing in industrial hygiene and the west­ern regional director for the Chemical Hazard Information Program (CHIP) at Cornell University, the standard for salons is 25 cfm/person. For a salon with 35 employees and clients, this means a ventilation system should bring in 875 cfm of fresh air.

Says Brown, “General office building standards are 20 cfm/person; 25 cfm is substantially higher. If you’re an independent contractor, it’s important to ask about ventilation before you rent space in a salon. You need to be certain the system is operating the way it’s supposed to.”

AIRBORNE POLLUTANTS

Brown, author of Health Hazard Manual for Cosmetologists, Hairdressers, Beauticians and Barbers, says the importance of building ventilation can’t be stressed enough. “Young people think they’re indestructible,” she says. “We’ve seen salon case histories of skin irritation from particulate matter in the air. Washing your face frequently, using barrier creams, and wearing long sleeves and high-necked clothing minimizes this. But the biggest problem in salons is inhalation of particulates and pollutants. We’ve seen a marked decrease in lung function as a result.”

Nail technicians need to be concerned about vapors and particu­lates from other products in the salon — hairsprays, aerosol prod­ucts, and asbestos in some hair dryers — as well as from their own chemical services. Any particle less than 5 microns is respirable (capa­ble of being inhaled), and most hairspray particles are less than 1 micron. (The state of California is currently regulating Volatile Organic Compounds [VOCs] in hair- sprays and other products.)

It’s important to remember that it is the accumulation of particulates and vapors and their proximity to the area two feet around your mouth and nose (your breathing zone), coupled with ineffective or nonexistent ventilation, that you should be concerned about. It is not the simple existence of chemicals that is dangerous. Truly hazardous chemicals are banned by the FDA, as in the past case of nail hardeners containing more than 5% free formaldehyde, and methyl methacrylate in nail products. The goal is to minimize your exposure to chemicals, not necessarily to rid the salons of them altogether.

With this aim in mind, Brown points out that locating supply and exhaust vents of HVAC systems too close together simply moves contaminated air back and forth.

ENERGY SAVERS

Air brought in from the outside must be cooled or heated, and cost-conscious building owners will sometimes operate HVAC systems below standards in an effort to save money. Recognizing that some building owners will take dangerous shortcuts, engineers have been working on more cost- effective heat exchangers. Semco Manufacturing of Columbia, Mo., has offered the “newest” fresh air with energy recovery technology since the 1970s, but it’s been used primarily in hospitals, where the need for ample fresh air is essential. Now, die system is being scaled down for small-building use.

The system transfers heat and moisture, which cools air, from the exhaust air to the incoming air. The adsorptive material used in the transfer allows airborne contaminates to pass through but holds water vapor. (Adsorb means that gases or vapors “stick” to the surface, rather than getting soaked up or absorbed.) In winter, the warm water vapor is mixed with the fresh incoming air, reducing the need to heat that air. In summer, the heat and moisture from outside air is transferred to the exhaust, reducing cooling and dehumidification requirements. The result is that the energy demands on heating and air conditioning systems are considerably reduced.

Mike Boles, Semco’s product manager for systems, says, “By the end of 1992, a scaled-down version will be available for commercial space. Currently, the hospital systems cost $3,000 to $50,000. The smaller version ventilates at levels well above standards for salons, op­erates at 80% energy savings, and will cost under $2,000.”

TIPS FOR BETTER BREATHING

Another important HVAC system consideration is whether you can adequately ventilate from your location. According to Wayne Turett of Turett Collaborative Architects in New York City, “What you can ventilate and how far away is regulated. In New York City, your exhaust vent must be at least 12 feet away from anyone else’s window if you’re venting vapors. If you’re in a storefront and someone lives above you, you can’t exhaust fumes.”

This advice may come too late for salon owners who selected a site not originally designed for salon work, but this is an important consideration if you’re scouting a new location. Check your local requirements first. For instance, an Ohio nail salon moved its exhaust vent so that it was aimed directly at the intake vent of a pizza shop nearby. The salon was forced to move its exhaust vent immediately and the experience turned formerly friendly neighbors into enemies.

According to Turett, larger buildings often have existing systems you can connect into, but shopping malls can pose special problems. Al Buettner of Air Filter and Equipment Co. in Chicago recently installed a ventilation system in a mall. ‘There was a nail salon in the mall that everyone complained about,” he notes. “They were not against an outside wall so they couldn’t exhaust fumes. You could smell them for a long way.”

Smelly fumes may be a nuisance to neighboring shops, but they’re far worse for salon employees. While odors may be unpleasant, hiding them or masking them does not eliminate the vapors. When looking for a new salon or evaluating your current location’s vent system, find out if it permits exhausting to the outside; if not, it is not a suitable location for a salon.

When you investigate HVAC systems, be aware of the following EPA guidelines:

• Do not disrupt airflow with partitions or other barriers.
• Maintain proper temperature and humidity, otherwise employees may block vents and supply registers if they feel too hot or cold.
• Do not position air supply vents near sources of outdoor pollution, such as heavy traffic, chimneys, or trash deposits. If you do, the air you bring in could be worse than what you’re exhausting.
• Turn on your ventilation system several hours prior to occupancy. If you leave it off at night and on weekends and turn it on only when you start working, pollution levels will increase.
• If you own the building, maintain your system. HVAC systems can clog, and accumulations of water anywhere in them can foster harmful biological growths.
• Keep records of all HVAC system problems and have routine maintenance and inspection performed Document any employee complaints, they could help solve problems later;
• If you suspect that there’s a problem with your HVAC system, call your State Health Department and request an air survey.

Betsy Agle of the EPA Public In­formation Center says, “It’s hard to get government personnel to test your air. Then, if harmful chemi­cals are present, there may be no standards to test against. OSHA (Occupational Safety and Health Administration) has its own levels, but they were set with steel mills and chemical plants in mind so they may not be helpful to commercial establishments.”

ADJUNCT VENTILATION SYSTEMS

In addition to HVAC systems, which are essential for all commercial buildings, adjunct systems in the form of air cleaners, filters, and spot ventilators are important to salons to ensure worker health and safety.

According to John Meagher, a certified industrial hygienist and manager of government and technical affairs for the American Industrial Hygiene Association (AIHA), both source control and spot ventilation are important in nail salons because the chemicals technicians work with affect indoor air quality and have the potential to cause health, comfort, or odor problems if not ventilated properly or if inhaled.

Filing dust poses similar problems, particularly if you use high speed filing systems, which produce much smaller particles than manual filing. AIHA advises against using drills that create small, easily inhaled particles.

“Lachrymators attack mucus Source control requires limiting membranes and dissolve the skin at low levels,” says Meagher. “They chemically change protein; our skin, hair, and nails are protein. Many of the materials used in hair and nail salons are irritating to the eyes, nose, and open cuts.” Acrylates found in glues and other nail chemicals are lachrymators.

Patrick Rafferty, technical director of industrial hygiene at Roy F. Weston environmental consulting firm and chairperson of AIHA’s indoor environmental quality committee, adds, “Dust and particulate matter must be vented out of a building. You can use an electrostatic precipitator or HEPA (high-efficiency particle arrestor) filters, depending on the size of the particles. The shape and chemical composition of the particle is not critical to a choice of removal systems. On the other hand, the only way to get rid of organic pollutants like gases is to catch them on adsorptive carbon or exhaust them out of the building.

“Nail salons need good ventilation systems, source control, and place the mask daily, be­cause it spot ventilation. The closer your ventilation system is to the source where pollutants are generated, the more efficient it can be. You need to intervene with the air movement between the hand and the nose or mouth.”

Brown is even more specific. In Health Hazard Manual for Cosmetologists, Beauticians and Barbers, she notes that both patron and manicurist are exposed to dust and solvent vapors dining a nail service, but it is the professional who gets repeated or prolonged exposure. “Studies indicate that approximately 20% of hairdressers leave the profession due to health problems such as allergies and dermatitis,” she says. “After an investment in time and education, people shouldn’t have to leave a profession.”Nail products contain solvent-based vapors that must be captured to be removed. Working in a hooded device with a ventilated table that uses an activated carbon filter and exhausts to the outside removes these vapors where they’re generated. This works very well in conjunction with good, general room ventilation that meets the standards recommended by ASHRAE,” continues Brown.

To understand the need for adjunct ventilation, read Material Safety Data Sheets (MSDS) for the chemicals you are exposed to to ensure that you are using your products correctly. Understanding the warnings on the MSDS will help you avoid allergic reactions and inhalation of dust and gases.

Experts agree that exhausting to the outside and using spot ventilation are the best ways to ensure worker safety. Some specific knowledge about air cleaners and local ventilation systems is vital for salon owners and employees. Keep in mind that many of the chemicals used in salons have no set safety standards, so for now, minimizing exposure is the aim.

AIR CLEANERS AND PURIFIERS

The three primary types of air cleaners or purifiers are ozone generators, ion generators, and electrostatic precipitators. These systems purify the air by removing dust and particulate matter. The EPA notes that air cleaners can remove gaseous pollutants only if the clean­ers contain activated charcoal.

Ozone generators create molecules of oxygen (O3) that react with chemicals to transform them into harmless gases under controlled laboratory conditions. However, they are not predictable in salons. In addition, according to the EPA, ozone is a lung irritant, and exposure levels must be controlled.

Ion generators, also called negative ionizers, electrically create negatively charged ions, which in turn, attract positively charged particles in the air. When the two collide, the particle is knocked from the air or drawn downward by gravity and settles on a surface.

Electrostatic precipitators draw air into a “trap” of electrically charged plates. Particles then adhere to the plates and are removed from the air.

“Electrostatic precipitators work well for eliminating cigarette smoke, particulate matter, and fine aerosols,” says Meagher. “They will not work for true gases because of their molecular size. Acrylates are molecular and true gases, so electrostatic precipitators will not work with them.” Both ion generators and precipitators must be cleaned regularly.

Bridgers claims her allergy problems disappeared when she began using a large negative ionizer.

FILTERS FOR LOCAL VENTILATION

According to the experts, nail technicians need to trap particles and vapors before they enter the breathing zone. The systems available for doing this generally combine a HEPA filter and an activated carbon or charcoal filter. Controlled suction or airflow draws particles and vapors into these filters.

HEPA filters are pleated to trap dust, filings, and small, respirable particles. Flat mechanical filters will collect only large particles.

Says Rafferty, “If the Colorado standards (see sidebar) are 0.3 microns, HEPA filters stop particles smaller than a nail technician needs. If they are hooked up properly and have pre-filters, they work well, but you must replace the filter regularly.”

Dust masks are an effective and inexpensive way to avoid inhaling particles. While many technicians are put off by their “industrial” appearance, dust masks will become more accepted when more safety-minded salon workers start wearing them.

Activated carbon or charcoal is the only thing that will trap true gases. According to Meagher, the terms charcoal and carbon are often used interchangeably and there is no real difference. However, since charcoal is larger than carbon, which is very fine, carbon is the preferred filter material. The key word for carbon effectiveness is activated.

“Activated means the carbon has been treated with heat, which creates more pores on the surface,” explains Meagher. “This is what makes the carbon adsorptive. Also, the finer the carbon, or the greater surface area it has, the more adsorption you get.

“Think of an ice cube with six sides. When you cut it in half, you have twice as many sides, so twice as much surface area. With carbon, this translates into a greater capacity for adsorption. While fine carbon is harder to clean than pellet- sized material, it’s much better because it adsorbs more.” The density of the filter is also important. Loosely packed carbon does not have the adsorption capacity of densely packed carbon.

Bob Nevin of Nevin Company in Chicago, a manufacturer of dental lab benches, has tested some of the ventilated manicuring tables on the market and found them ineffective because the carbon filters were inadequate. “Granule size of activated carbon is most important; the airflow is next most important,” he asserts Nevin is currently considering modifying equipment used in dental labs for the salon industry, since many of the same chemicals and acrylic resins that are used in salons are used in dentistry.

Before setting its standards in 1986, the Colorado state board also found that the tables it tested did not house a big enough filter to meet its air standards. Effective systems should use at least five pounds of very fine-sized, densely packed carbon. Meagher adds, “For good adsorption, the carbon should be so fine it looks gray and grimy.”

LOCAL VENTILATION SYSTEMS

Carbon and HEPA filters work when a motor-driven fan pulls air through them. The rate of airflow is an important factor in any system. If die airflow is too strong it can affect the products a nail technician is using; polishes could dry before they’re supposed to, and liquid and powder systems may set up too quickly. In addition, vapors will be pulled through the carbon too rapidly to be adsorbed. Particles need at least one-tenth of a second to collide with and adhere to the adsorptive material. If airflow is too weak, the pollutants will not be captured before they enter your breathing zone. The airflow in an effective system should be capable of capturing 50 to 100 feet of air per minute.

In addition, airflow should pull pollutants down, not upward across your breathing zone. “Exhaust hoses should be located at the height of the table or just below it,” says Brown.

A down-draft system that vents air very close to your hands or one that attaches to the table through a hole in the bottom will meet this requirement. However, you’ve got to work right over the vent s grill to get the full effect of this system.

EXHAUSTING DECISIONS

Ideally, after being pulled through carbon and HEPA filters, air should be exhausted to the outside. Attachments for ventilated tables use a hose that leads to an exhaust vent. You can also find listings in the phone book under “heating and air conditioning” if you need a custom exhaust system. A reputable engineer should be able to fashion such a device easily and inexpensively.

Most regulated industries that use chemicals or produce fumes and vapors also use local exhaust systems. Welding applications, for instance, use local exhaust systems where a flexible hose is brought from a duct to the work area under a hood. However, sys­tems like these are much larger than salons need and would require extensive modifications, since their powerful suction could suck your hand right in.

ENCLOSED SPACE

Protective hoods are a proven solution for local pollution problems in industries from steel mills to dental labs, and offer excellent ventilation options in salons as well. Meagher observes, “As an industrial hygienist looking at a salon, I’d recommend a small Plexiglas hood that the hands go underneath. Resting the hands on a pad should start the ventilation. This is the best and cheapest way to deal with acrylates.” Considerations regarding the type of ventilation you need include whether or not you use many acrylates in a short time, the airflow rate of your ventilation system, and other chemicals entering the filter.

“Hoods help because suction is less effective with distance,” adds Nellie Brown. If you contain the area of contaminates and use an efficient exhaust system, you won’t breathe slow-falling particles when your face is close to a work area.”

Protective hoods are particularly good for contact lens wearers, although most of our experts said nail technicians should not wear contact lenses in the salon, especially soft: lenses, which have a high water content and quickly absorb vapors and airborne materials.

SYSTEM MAINTENANCE

How often you should change filters depends on their size and capacity, and the density and size of the carbon. Says Meagher, “Recirculating systems can easily overload if they’re not changed. It’s like putting a hole in a vacuum cleaner. But with proper maintenance, they can work Whether or not you vent to the outside depends on the materials you’re using.”

If your system has a filter under five pounds, and particularly if you do not vent to the outside, a rigorous maintenance schedule is essential. Carbon continues to absorb even when the fan is not on, and many salon owners don’t change the filters as often as they should because they aren’t counting this time in the maintenance schedule. But, warns Rafferty, “Once you reach a certain limit, the filters are no good and can even harbor bacteria and mold that get into the air stream.”

While the average recommendation for changing the filter is once a month, this guideline doesn’t take into account the frequency of usage, types of chemicals present, or the amount of chemicals in the air. A San Diego University study of six nail salons to measure worker exposure to toluene, isopropyl alcohol, butyl acetate, ethyl methacrylate acrylic, and other chemicals indicated that tables with activated charcoal beds had no effect in terms of reducing ethyl methacrylate vapor levels because salon owners had not changed the filters in five months.

COSTS

Although industrial hygienists recommend local ventilation systems for nail salons, surprisingly few have them. Murray Stern of Emiliani Beauty Supply of New York notes that only 10% of the manicure tables the company sold in the past year had ventilation systems.

The primary reasons many owners and technicians give for not having vented tables are cost, doubts that they worked if they did not vent air to the outside, and a misplaced belief that HVAC systems provide adequate ventilation. One salon owner felt that open windows were adequate for healthful breathing. As more state boards take aggressive action and as education about ventilation systems continues, these attitudes may change.

ELIMINATE CONFUSION

When investigating ventilation systems, don’t be misled. Measure any purchase against standard guidelines and ask for proof of a system’s claims when in doubt. Pay particular attention to the size and density of carbon filters and to airflow rates. Understand what works for particles and what works for vapors before you buy. Don’t be afraid to ask your state board or an industrial hygienist for help and information. With so many industries working with HVAC and local ventilation systems, no one has to reinvent the wheel because the best solutions to pollutants, particulates, and vapors are universal in the engineering world; it’s only the standards that are individual.

“Stick to proven solutions,” says Meagher. “Limit your usage of pollutants and vent building air to the outside. Next, use filtration in the form of activated charcoal and HEPA filters with local exhaust.”

If you work safely there’s no reason you can’t enjoy your profession for a lifetime.

 

SOURCE CONTROL AND SAFETY

Source control requires limiting the amount of chemicals in the air in the first place, while safety means developing sensible, daily practices. Try to make the following guidelines a habit.

• Keep bottles tightly closed whenever they are not in use. Uncapped bottles can spill or allow vapors to escape.
• Store chemical products in cabinets in a cool area when not in use. Acrylates evaporate over a long period of time. If they spill, containing the vapors helps.
• Do not wear contact lenses when working in a nail salon.
• Use barrier creams to keep products off your skin.
• Wear a dust or surgical mask when filing. Replace the mask daily, because it loses its effectiveness quickly.
• Don’t smoke in the salon. Cigarette smoke contributes to air pollution, and many nail products are flammable.
• Read Material Safety Data Sheets. Know what the signs of chemical overexposure are and know what to do in case of an emergency or a spill.

COLORADO’S STAND

Colorado’s state board was the first one to set ventilation standards for nail salons, and their guidelines are worth reviewing by nail technicians in all states. The regulations, which became effective August 1, 1986, are as follows:

1. The system must circulate air adequately in direct proportion to the amount of space where artificial nails are applied.
2. Air must be completely exchanged six times per hour.
3. Any filtration system must be able to remove particles as small as 0.3 microns.
4. A charcoal filter compatible with the size of the unit must be used in conjunction with the dry media or electrostatic system.

Since the board found that no table then available was strong enough to meet its guidelines, it requires state nail salons to install air purifiers that have been tested and meet their guidelines.

WHAT DOES CLEAN AIR COST?

To give you an idea of what available systems cost, here’s a brief sampling. When selecting a system, ask for proof that it meets Colorado standards or has been tested by a certified industrial hygienist and compares favorably to established guidelines. Use and maintain any system you buy according to the manufacturer’s directions.

Ventilated tables. Kayline Enterprises offers complete ventilated nail care centers from $550.95. Filters should be changed every six weeks and cost $6.40 each, according to the manufacturer. For more information call (310) 5954515.

At Professional Fabricators by Touchi, tables with HEPA and activated charcoal filters start at $547. According to the manufacturer, filters last for approximately four months and cost $15 each, For more information call (714) 761-3713.

Local Ventilation Fume Extractors. Lab Safety Supply in Janesville, Wis., sells local exhaust systems for a number of industries with pollutant situations similar to salons. One model looks like a desk lamp, draws air upward when you place your hands under it, and contains activated carbon in the lamp “neck.” Fume extractors range from $700 to $2,000. A call to the company will get you a catalog. The company does not make recommendations, so you must take the catalog to an industrial hygienist to discuss the volume of contaminants and airflow requirements in your salon. While this may seem inconvenient, it’s one way to ensure suitability. For more information call (800) 356-2501.

Adaptable Systems. If you already have a manicure table, the Work Top Air Cleaner can be installed by drilling a 1/8- inch hole in the tabletop or by cutting a hole through the glass. It contains a HEPA filter and an activated charcoal filter and is rated to move 140 cubic feet of air per minute. Cost is approximately $230 plus shipping. The manufacturer also offers automatic filter mailing, in case you forget to order. Three months’ supply: $24.95. For more information call (800) 422- WTAC or (407) 283-2623.

In addition, look under “heating and air conditioning” in your local phone book and ask about custom-designed local exhaust systems. Costs will vary by state and establishment, and a small firm may offer the most competitive pricing.

Protective Hoods. Hood innovations offers a hood alone for $249, which adapts to an existing filtration system or a hood with carbon and HEPA filters for $529. According to the manufacturer, the hood meets Colorado state guidelines and has been tested by an industrial hygienist. The hood is 22 inches side-to-side, 17 inches front-to-back and 11 ½ inches high. For more information call (619) 274-1435.

Air Cleaners. Salon Aire offers three models of combination low-level ozone and ion generators that handle from 1,000 to 2,000 square feet, for average to heavy-duty pollution conditions, according to the manufacturer. They are priced from $629 to $895. For more information call (803) 842-7427.

Electrostatic Precipitators from Janays cover 1,200 to 1,500 square feet, according to the distributor, and cost $175. For more information call (714) 465-1415.