Whether in a sawmill, an industrial workplace or a research laboratory, the danger associated with workers getting hazardous substances in their eyes or on their skin should never be underestimated. Emergency eyewash and shower equipment is an integral part of any company’s response system, since certain chemicals can cause eye damage and even loss of sight. Any splashing incident requires flushing immediately.
The Canadian Centre for Occupational Health and Safety (CCOHS) in Hamilton, Ontario suggests that workplaces containing battery-charging stations, laboratories, spraying operations and hazardous-substance dispensing areas could all make use of eyewashes, eye-face washes, emergency showers or a combination of these devices.
In the absence of a homegrown standard on the design, placement and use of such equipment, Canadians seeking guidance may turn to the American National Standards Institute (ANSI) in Washington, D.C., which released a revised eyewash/shower standard in 2009.
ANSI standard Z358.1-2009 was prepared by the Arlington, Virginia-based International Safety Equipment Association. Its specifications are fairly straightforward: eyewash and shower equipment must be located within 10 seconds of wherever a worker could be exposed, notes Michael Markovsky, chief operating officer of Haws Corporation in Sparks, Nevada. “It has to be unimpeded access, so you can’t have to hop over things or walk around obstructions,” Markovsky says. Once at the station, a worker needs to flush the affected area for a full 15 minutes.
Beyond these basics, the revised standard clarifies some of the more nitty-gritty aspects of the equipment and its uses. Among the most significant changes is an updated explanation of appropriate fluid temperature for emergency fixtures. The previous version of the standard (circa 2004) specified that an eyewash or shower’s flushing fluid should be “tepid.” Now, the standard specifies a temperature between 15 and 37 degrees Celsius.
But not all work environments are at the same temperature, so equipment must suit its surroundings. For colder outdoor settings, for example, it might be worthwhile to invest in portable freeze-proof units. Markovsky notes that when a worker comes into contact with a hazardous substance outdoors, it would be especially difficult to achieve the 10-second requirement set out in the standard if units were restricted to indoor environments.
Claudio Dente, president of Dentec Safety Specialists, Inc. in Newmarket, Ontario, says his company offers freeze-protected, gravity-fed units and freeze-protected shower units.
Sometimes, though, the problem is just the opposite: work environments can get too hot to ensure the temperature of emergency fluid remains within the acceptable range. The CCOHS lists foundries, steel mills, smelters and glass factories as possible candidates.
“Anything beyond [37°C] that you’re putting into your eyes, you’re running the risk of damaging eye tissue,” explains Markovsky. In addition, there is “equipment that actually has refrigeration or chilling involved with it. We refer to it as reverse tempering, where people are cooling water rather than heating it” to get within the 15-to-37°C range, he adds.
In the flow
Over the past decade, advancements have been made surrounding flow control in eyewashes, eye-face washes and emergency showers.
Most eyewashes, Markovsky says, expel arced streams of water directed at one another, which allow the water to contact the outer corner of the eye and run toward the nose. He argues that this “traditional approach is 180 degrees different” from the medical community’s method of eye irrigation, noting that his company offers products that provide a more medically efficient flow pattern, in which the solution hits the inner corner of the eye and flows outward.
“There are things called lacrimal puncta, which are little holes in your ocular cavity that are adjacent to the bridge of your nose, and those holes drain excess fluid out of your eye cavity,” explains Markovsky. However, with the traditional method, the hazardous material is flushed into the affected worker’s nasal cavity, possibly leading to ingestion.
When purchasing emergency fixtures, consumers must consider the pressure and impact of the water flow. Line pressure in eyewashes can be anywhere from 30 to 100-plus pounds per square inch (psi), says Markovsky, noting that ophthalmologists have told him that when an eyewash is running at a very high line pressure with no flow control, “it would be a torture test for someone who’s not injured to stick their face into one of these things and stay there for 15 minutes, with water blasting against [their] eyeballs.”
But eyewash water pressure can also be too low, causing the fixtures to function improperly. Emergency fixtures must be 30 psi at the point of entry, and workplaces would be well advised to ensure their systems do not have high pressure drops, which would cause water pressure to be too low on impact. But whatever the pressure, keeping one’s eyes under an eyewash for 15 consecutive minutes is bound to be uncomfortable. “It can hurt if it’s too hard or if you’re using a spray head or a traditional spray,” Dente comments.
To make the process more bearable, Dentec offers an aerated spray head that softens water flow. The head “throws billions of bubbles at the eyes so it’s easier — although still uncomfortable — to hold your eyes open and stick [them] under the water,” Dente says.
In addition, some equipment makers are exploring new water-delivery methods that tweak nozzle size and placement in emergency showers.
Jim Johnson, general manager of Encon Safety Products in Houston, remarks that the ANSI standard now allows for multiple nozzles to be located at the sides of the shower as well as above the user’s head.
“The overhead shower serves a great service for full-body drench coming down, but there are situations when someone may be affected by a spray that was in an upward motion,” Johnson notes. “[If] they’re affected under the armpits, in the groin or mid-body area, maybe under the neck, [then] water being projected from the sides helps address those concerns a little better than the overhead shower does.”
Beyond nozzle placement, product designers are experimenting with different nozzle sizes to provide a more thorough wash-down. Over the past 30 years, a showerhead of 25 centimetres in diameter has been the standard size to provide an evenly dispersed flow. But with technological advancements and new knowledge surrounding fluid dynamics, that larger showerhead is no longer necessary, as several companies now offer smaller nozzles that more effectively concentrate flow and provide a faster wash-down.
When determining what type of eyewash unit to buy, one fundamental decision will be whether the purchaser should choose a portable, self-contained unit equipped with either stored water or a sealed cartridge of eyewash solution, or a plumbed unit connected to a local water source.
Before choosing, a company should first consult relevant material safety data sheets (MSDSs) to learn about the properties and potential risks of any chemicals to which workers may be exposed. Employers should periodically do a walkthrough analysis of the workplace to ensure safety measures are still applicable. Portable systems are often used where plumbed water is not available, and many consumers are looking for stations which can be moved around operations.
Possibly more divisive than “portable versus plumbed” is the question of what constitutes the best flushing fluid. The CCOHS notes that ANSI defines an acceptable flushing fluid as “potable (drinking) water, preserved water, preserved buffered saline solution or other medically acceptable solutions.”
Despite the concerns surrounding potable water, many manufacturers recommend it as the most reasonably priced and reliable flushing source. “It is already meeting Health Canada requirements because it’s going to be ingested,” Dente says.
From a cost perspective, Markovsky points out that refills for gravity-fed units are much more expensive than municipal water. But his most pressing concerns with sealed cartridges are the safety risks — if the sealed cartridge has been used and not yet replaced, it can leave a gap of time in which a workplace will have no fluid to deal with any eye injury that might occur. “That’s a dangerous situation,” he says.
Another option, one that is close at hand, is the personal eyewash, squeeze bottles containing a small amount of saline solution. “We package a 32-ounce [0.9-litre] bottle, and it’s used for very quick, personal washes,” says Johnson, who cautions that while these bottles offer a temporary remedy, they are not to be used in place of a standard eyewash unit.
“A lot of workers like that safety factor or that crutch of having a personal wash station where they can just reach and grab it and start addressing the injury on their way to the shower and eyewash,” he suggests.
The hope is that a workplace will seldom need to make use of an emergency eyewash or shower. Nonetheless, plumbed systems should be activated regularly for maintenance. It helps to let the water run on a weekly basis so that in the event of an emergency, the system is ready to dispense fresh water. In addition, Dente suggests, the wash system should be run by employers for a full 15 minutes once a year, as specified in the ANSI standard.
Ultimately, it is crucial to ensure employees understand what the equipment is and why it is necessary. Training on emergency fixtures should be done twice a year to accommodate new employees and those whose roles might have changed. The employer should have sufficient training as well.
Emily Landau is a former editorial assistant of OHS Canada.