What kind of idiot would put acid into bottles like this? the man fumed, pushing his safety glasses up on his brow to get a better look at the problem. He picked up the bottles to show his supervisor on the other side of the yard.
Suddenly, the bottle in his left hand slipped. Glancing down, the man was relieved to see that it was unbroken, but from the center of the container, a single drop flew upward into his eye.
His scream drew coworkers, who forced him to his knees, prying his hand from his eye and pulling the eyelid upward. They irrigated the eye with water from a hose as the supervisor called for help.
Paramedics continued irrigating en route to the emergency room, and the soaking continued at the hospital. Hours later, the man was sent home.
Two weeks later, his vision was as it had been prior to the accident. Decisive action by his coworkers saved his sight.
Consultant Neil Langerman, Ph.D., of Advanced Chemical Safety in San Diego, tells this story to illustrate that accidents are caused by a series of events, any one of which, if it had not occurred, would have prevented the accident.
Chemical splash accidents are a sterling example of this theory. Engineering the hazard out of a problem (e.g., properly storing the acid) normally is sufficient prevention. Administrative controls, such as warning other employees away from the improperly stored acid and bringing the hazard to the supervisor's attention (rather than carrying the bottles), also prevent accidents. In this case, training was sloppy: the employee let down his guard, did not have his personal protective equipment (PPE) in place and almost paid with his eyesight.
Despite decades of effort to eliminate them, occupational eye injuries remain a widespread and costly problem.
"We have traditionally used the annual figure of 356,000 eye injuries of all types in the workplace," says Todd Turriff, vice president of Prevent Blindness America, a 90-year-old nonprofit organization dealing with health-related vision problems, including safety issues. However, the Chicago-based agency anticipates a NIOSH report, due this summer, that will identify between 650,000 and 700,000 workplace-related eye injuries, based on workers' compensation claims.
"One-quarter of those injuries will result in permanent disability," Turriff says. "That's when the individual loses at least one full day of work from dust and debris, from injurious light sources such as welding flashes and electric arcs, and from chemical splashes.
When chemicals splash in the eyes, it is natural to close them to avoid further injury, yet closing them is the surest way to destroy eyesight. Acids burn initially when they contact the eye, then precipitate protein in front of the eye.
Alkali splashes are potentially more damaging because alkali leaches water from the tissues and continues to burn through them. Closing the eyes seals the chemical under the folds of the lids, allowing the molecules to bond with water, fueling the burn. "Within seconds, the alkali will have penetrated the cornea and reached the iris, the lens, the vitreous humor, and the retina," explains John B. Jeffers, M.D., director of emergency services at the Wills Eye Hospital in Philadelphia. "In some cases, the entire eye is destroyed."
Corrosive gas molecules can combine with as little as 30 percent relative humidity in the air to form mists that irritate the eyes.
Likewise, acids, alkali, or solvents that contact unprotected skin burn rapidly through the tissue unless they are rapidly diluted with large quantities of potable liquid and the particulates flushed away.
"If you don't give it [the burn] lots and lots of water, typical water-reactive industrial chemicals will take the water out of the person's system and will continue to do damage by dehydrating and burning," Langerman explains. "The faster you get water on it, the better. A little bit of water is devastating because it activates the chemical, but if you use enough water, it will flush that heat away." Both Langerman and Jeffers strongly advise flushing continuously until the victim is transported because chemical residue continues burning and the pH of the tissue can rise rapidly when flushing is discontinued.
Ideally, eyes should be flushed with a sterile, isotonic, pH-balanced solution at a temperature between 60 and 90 degrees F. Drench showers should use clean, uncontaminated water that is near body temperature. "Realistically, the quality of the water doesn't matter," Langerman says. "What matters is that you use lots of it." Both he and Jeffers point out that, in an emergency, any potable fluid, anything you can drink, can be used. "We can treat infections, but there is no way I can recover your sight," Langerman warns.
Finding appropriate shower and eyewash equipment may be easier than you thought possible. Robert Hurley, president of Fend-all, an Arlington Heights, Ill., manufacturer of eyewash stations, suggests starting with OSHA's hazard communication standard, 29CFR 1910.1200, which requires employers to identify and evaluate all chemicals used in the workplace. "Look anywhere in your facility where chemicals could splash in the eyes or come in contact with the skin. Then use material safety data sheets (MSDSs) to identify those chemicals that are hazardous," he says. The MSDS should tell you if the potential hazard requires proximity to an emergency shower or eyewash station.
Hurley points out, "Looking at the 1997 OSHA citations, the hazard communication standard was one of the top 10 items cited. Another [prominent] item was the lack of emergency shower and eyewash facilities." The Occupational Safety and Health Administration (OSHA) can cite companies at which hazardous chemicals are in use and in which emergency showers and eyewash stations are not present, accessible to those working with the chemicals, or in proper working condition. OSHA standard 29 CFR 1910.151, Medical Services and First Aid, states: "Where the eyes or body of any person may be exposed to injurious corrosive materials, suitable facilities for drenching or flushing the eyes and body shall be provided within the work area for immediate emergency access."
Having identified the operations in which hazardous chemicals prescribe the need for emergency shower and eyewash units, consult the American National Standards Institute's ANSI Z-358.1-1998 for emergency eyewash and shower equipment. This iteration by the Industrial Safety Equipment Association, Arlington, Va., updates the 1981 standard to include eyewash stations, emergency showers, drench hoses, combination units, and personal eyewash bottles and promulgates minimum performance standards for installation and use, training, and maintenance. "The standard is meant to protect the users," says Christine Fargo, ISEA technical projects coordinator. "But it is also a checklist against which manufacturers of this equipment can measure themselves."
What does the standard require (at a minimum) for features?
Plumbed and Self-Contained Emergency Showers:
- Shower heads should provide a column of flushing fluid that is, at minimum, 82 in. in height from the floor of the unit, with a minimum diameter of 20 in. at 60 in. from the floor of the unit. The center of the spray pattern should be 16 in. from any obstruction. The heads should deliver a minimum of 20 gallons/minute of fluid at a non-injurious velocity for at least 15 minutes.
- Valve actuators are to be easy to locate and use, and shall be located not more than 69 in. above the floor of the unit.
- Enclosed units will allow a minimum unobstructed area of 34 in. in diameter.
- Plumbed units must be tested weekly. All units are to be inspected annually for compliance with the standard.
- Plumbed and Self-Contained Eyewash Equipment:
- Flushing fluid should flow in a noninjurious, controlled pattern that reaches both eyes simultaneously at a minimum rate of 0.4 gallons per minute for at least 15 minutes. A suitable flow pattern is 4 in. long with two sets of parallel lines equidistant from the center.
- Nozzles should be protected from airborne contaminants, yet the protection should not impede its immediate use.
- Flushing fluid should be protected from airborne contaminants.
- Eyewash nozzles must be not less than 33 in. nor more than 45 in. from the floor and not less than 6 in. from the wall.
- Plumbed eyewash units must provide an uninterruptible supply of flushing fluid at a minimum flow pressure of 30 psi.
- Personal eyewash units must be filled with flushing fluid, should not be injurious when used, and must be regularly inspected and maintained.
- The noncorrosive control valve on both showers and eyewash units should open within one second or less from activation, should remain open without use of the user's hands, and should shut off only when manually deactivated. The control valve should be easy to locate and use.
- Users should be able to reach both showers and eyewash units, unobstructed, within 10 seconds from the site of the hazard. The units should be on the same level as the floor, and should be both easily identified and well-lit. In areas where a strong caustic or acid is present, the eyewash unit must be adjacent to that area.
Every employee who works with hazardous chemicals and every supervisor "should be trained to recognize hazardous materials, to understand where they are, to understand that flushing the eyes is the first step in emergency first aid, to know where the emergency eye stations are, and to properly use eyewash stations," advises Hurley.
Training, says Jim Johnson, business unit manager of shower and eyewash equipment at Encon Safety Products in Houston, should be part of employee orientation. "We recommend that user training on these units be part of your safety training program," he adds.
Prevent Blindness America offers information and referral services. Call 800-331-2020 or visit its Web site at http://www.preventblindness.org. Safety literature and videos on eye health and safety and the Wise Owl PPE safety program are available.
Maintenance personnel must be trained to test and service all eyewash and shower stations in accordance with the ANSI standard. All manufacturers offer videos or printed information demonstrating proper maintenance techniques. Copies of ANSI Z-358.1 (1998) are available from ISEA by calling 703-525-1695.
Having eyewash and shower stations does not excuse an absence of engineering controls, administrative measures, and PPE for preventing chemical accidents, but they are your best first response for averting permanent injury.