Aug 19, 2010
Posted on Aug 19, 2010 in Safety Glasses | 1 comment
Written on Tuesday, November 24, 2009
Polarized safety glasses help to prevent eye fatigue and reduce glare. This increases the ability to see, and increases overall safety in the work environment. Any jobs outdoors will usually require polarized safety glasses. When light shines off a surface, it becomes polarized. All light planes move in one plane. Normally, light moves on many planes until it hits a reflective surface. When you wear polarized safety glasses, only one plan of light passes through the lens reducing reflection.
This is what eliminates glare and eye fatigue. Vision is vital in any work environment to maintain safety. Polarized glasses are very common in construction and outdoor jobs where the sun is bright and there are many surfaces. Light becomes polarized off of surfaces into different components. There is more of a horizontal component that is reflected than a vertical component. This is what makes reflective light polarized.
In order to eliminate glare, polarized safety glasses need to be vertically polarized. If glasses were polarized vertically and horizontally, no light would be transmitted. Normal sunglasses only decrease light intensity using a uniform percentage. Polarized glasses eliminate reflection off of various surfaces. Polarization is maximized when the sun is approximately 37 degrees from the horizon. If the sun is too low or too high, polarization is not as affective. These glasses will not help you if you are staring directly at a light source. They are not intended to block UV rays or infrared light. Sometimes people think polarized safety glasses will work for welding. This is not the case and can cause serious eye damage. There are safety glasses specifically made to protect from the infrared light that a welder deals with.
Polarization is a benefit when light comes at you between 30 and 60 degrees. Many outdoors workers experience reflections from the road, water, vehicles, and more. This is where polarized safety glasses increase visibility and safety. Workers who wear polarized glasses will have greater clarity, color definition, and reduced eye fatigue.
Rule of thumb is that if you are working outside in bright light, polarized safety glasses are best for your situation. Glare can really affect the ability to see when clarity is crucial for safety. This is especially true when it comes to highway work. Workers need to keep themselves safe, but also think about the drivers on the road. If vision is hindered even for a moment, disastrous results could occur.
If you work anywhere outdoors, polarized glasses aren’t going to hurt. As with any dark tinted glasses, they are not recommended in low levels of light, or in weather conditions that may further impede vision such as snow and rain.
Once people know how polarization occurs, they then realize why polarized safety glasses should be used instead of regular tinted glasses for the sun. It is not so much about brightness and it is increasing clarity by reducing glare. Glare is what impedes vision the most while leading to eye fatigue.
Aug 19, 2010
Posted on Aug 19, 2010 in Safety Glasses | 2 comments
Written on Tuesday, September 22, 2009
You already know that safety glasses are a necessity for protecting your eyes from potential injury caused by impact or flying debris. You may even know the exact style you want, but do you know which lens tint is right for your application?
Clear Lenses are recommended for general purpose mostly indoor (and some outdoor) work environments where normal to low light conditions exist. These are the most popular type of lenses because of their low cost and high functionality. Another benefit of clear safety glasses are their ability to provide true color recognition.
Indoor/Outdoor (I/O) Lenses offer protection for both indoor and outdoor environments because they are light enough to wear indoors, but dark enough to shade you eyes in the daylight. These lenses can be described as being darker than a clear lens, but lighter than a gray lens. The I/O tint is ideal for a person who is constantly changing environments.
Polarized Lenses are ideal for outdoor applications because they block reflective glare so wearers see more clearly and experience less eye fatigue. Glare produced from snow, water, cement, ice and other reflective surfaces can cause “blind spots” that may impair vision. Polarized lenses prevent blind spots by blocking glare.
Amber Lenses are recommended in low light conditions where enhanced contrast is needed. Amber lenses are perfect for working at dawn and dusk, or on a hazy, overcast day. However, they are not recommended for night driving or bright light environments.
Gray or Smoke Lenses provide general purpose sunglass protection in sunny, outdoor environments. These lenses are great for landscaping, construction, utility workers, airplane pilots, transportation and many other applications.
Brown or Espresso Lenses are similar to gray/smoke lenses, but provide enhanced contrast and depth perception.
Mirror Lenses also provide general purpose sunglass protection, but feature an enhanced lens color. In addition, mirror lenses reflect light, reducing even further the amount of light that passes through the lens.
Vermilion Lenses sharpen visual acuity and provide a contrast similar to amber lenses. Some people prefer vermilion lenses for indoor applications because they are better are reducing glare from fluorescent and halogen lighting without compromising color perception. These are great for inspections because defects are easier to see. Vermilion lenses are not recommended for driving or for use as general purpose eyewear.
Blue Lenses are commonly used in work applications where there are high levels of yellow or sodium vapor lighting and glare. These conditions exist in the semi-conductor industry and sometimes in food processing plants.
Orange Lenses offer high contrast and low light image resolution. They are high visibility, and are perfect for target shooting or other activities where clarity is a must.
IR 3.0 and 5.0 Green Lenses block infrared (IR) light and are designed for certain welding affiliated operations such as brazing and cutting. These are the darkest lenses available.
Anti-Fog Coated Lenses are ideal for humid environments or when moving from one extreme temperature to the next. Anti-fog coatings are usually available on a variety of different lens tints.
