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Facts At Your Fingertips: Considerations for Selecting Protective Eyewear

| By Scott Jenkins, Chemical Engineering magazine

Selecting personal protective equipment (PPE), including safety eyewear, for the chemical process industries (CPI) depends on the hazards present in the facility where it is used. The following describes considerations for selecting eye and face protection based on the potential to injure the eyes or face. Some examples of eye and face hazards and typical sources are summarized in Table 1.

Source: U.S. Dept. of Labor, Occupational Safety & Health Administration (OSHA)

In general, any eye and face protection should be comfortable to wear, sized correctly (if different sizes exist) and should not interfere with the employee’s work functions. Poor-fitting eyewear will not afford the necessary protection, may be uncomfortable to wear, and may not be used consistently and effectively.

Impact hazards. Safety spectacles are intended to shield the wearer’s eyes from impact hazards, such as flying fragments, objects, large chips and particles. Whenever there is a hazard from flying objects, workers are required to use eye-safety spectacles with side shields. Non-sideshield spectacles are not acceptable for impact hazards. Safety goggles are also intended to shield the wearer’s eyes from impact hazards. By fitting the face surrounding the eyes and forming a protective seal around the eyes, goggles prevent objects from entering under or around the goggles.

Face shields. Face shields do not protect employees’ eyes from impact hazards when worn alone, and should be used in combination with safety spectacles or goggles for additional protection. Faceshield windows are made of varying types of transparent materials and in varying thicknesses, both of which should be considered when selecting face shields for specific tasks. Window and headgear devices are available in various combinations to be compatible with other PPE, such as hardhats. Welding shields provide eye and face protection from flying particulate matter during welding, thermal cutting and other hot-work activities. These shields are typically equipped with shaded lenses that provide protection from optical radiation.

Heat hazards. Working with heat requires goggles or safety spectacles with special-purpose lenses and side shields. However, many heat-hazard exposures require the use of a face shield in addition to safety spectacles or goggles. When selecting PPE, consider the source and intensity of the heat and the type of splashes that may occur in the workplace.

Chemical hazards. Safety goggles protect the eyes, eye sockets, and the facial area immediately surrounding the eyes from a variety of chemical hazards. The protective seal formed around the eyes is especially important when working with or around liquids that may splash, spray or mist. Several kinds of cover-type goggles are available: direct vented, indirectly vented or non-vented. Vented goggles may be less effective in protecting the eyes from splashes and respiratory aerosols than non-vented or indirectly vented goggles. Face shields are intended to protect the entire face from a variety of chemical hazards, particularly when pouring chemicals or where splashes may occur. Face shields are considered secondary protection and must be used in addition to safety goggles to provide adequate protection.

Dust hazards. Working in a dusty environment can cause eye injuries and presents additional hazards to contact lens wearers. Safety goggles should be worn when dust is present. Safety goggles are the only effective type of eye protection from nuisance dust.

Optical radiation hazards. Welding, thermal cutting, brazing, laser work and similar operations create intense concentrations of heat, as well as ultraviolet, infrared, and reflected-light radiation. Some of these activities can produce optical radiation intensities greater than those experienced when looking directly at the sun. Unprotected exposure may result in eye injuries including retinal burns, cataracts, and permanent blindness. Many lasers produce invisible ultraviolet and other forms of non-ionizing radiation. The Occupational Safety and Health Administration (OSHA) standard 29 CFR 1010.133* includes a table that lists the minimum shade requirements for eye protection during industrial processes that generate optical radiation. The selection of eye protection for lasers should depend on the lasers in use and the operating conditions, and should be consistent with the laser manufacturer’s specifications.

PPE and prescription lenses. If employees wear reading glasses with basic magnification, American National Standards Institute (ANSI; safety glasses and goggles with reading magnifiers in the lenses are an option. Prescription safety glasses and goggles that are compliant with the ANSI standard are also available, as are ANSI-compliant goggles and safety glasses to fit over prescription glasses.

Editor’s note: Content for this column comes from the following article: D’Amato, Victor J., Eye-and-Face Personal Protective Equipment, Chem. Eng., February 2009, pp. 48–51.