Within Process industries and Construction Projects, there are numerous hazards within the environment, which cannot be eliminated. Hazards like dust particles and radiations are quite common and some like metal chips and chemicals splash are application based. To protect us from these hazards, we need appropriate safety eye wear. But based on the application and environment, various models of safety spectacles, goggles are designed and manufactured.
There is a difference in construction as well as application of goggle and spectacle. In case of spectacle the lens are mounted on a frame with temples.
In case of goggles, lenses are mounted on shroud and completely sealed around the eyes. The Goggles have headbands for better fit.
Generally Polycarbonate is used for lens of safety eye wear. Since due to its virtue of properties, offers UV resistant (99.9%). The strength of polycarbonate is very high and at the same time flexible for moulding process. Options like acetate are also used for niche applications for lens of safety eye wear. As per BIS & EN UDYOGI eye wear optically class I (± 0.06 diopter) and allow minimal refraction, thereby offering best vision.
Properties of polycarbonate are inherently prone to scratches during working conditions. So to reduce scratches and make it durable, manufacturers use a chemical coating known as Scratch Resistant Coating. The alternative name of Scratch Resistant coating is Hard Coating.
Our eyes breathe. Since safety spectacles need to be worn for long hours, the inside of lens gets fogged. Manufacturer’s use appropriate chemical coating inside the lens to restrict fogging. This coating does not affect or distract any vision. This coating is also anti-allergic. This coating is called anti-fog.
Anti-fog safety spectacle should be used in humid shop floors.
As per BIS & EN, the safety spectacles are tested at various speeds with a steel ball of 6mm diameter, 0.86 grams weight.
- Test is done at 45m/s and marked as F, it’s for spectacle.
- Test is done at 120m/s and marked as B, it’s for goggle.
General Prescription glasses are not tested to impact resistant, do not protect from UV and even not designed to be safe in the workplaces. There are specially designed over the prescription spectacles (which are compatible and seamless to wear over the prescription glass) should be used.
No, for proper protection against molten metal, it should be tested and marked 9 (as per standard, area of application), as the impact of molten metal would be higher. For this application it’s better to go for face protection.
By BIS & EN standard, the area of application of goggles can be where eyes are exposed to medium speed flying objects or chemical splash hazards etc. like in grinding operation, in labs. As goggles are air tight, covered sealing, can resist from medium impact hence workers perspires inside the eyewear. This perspiration over the eyes obstructs vision. So the goggles are provided with engineered ventilation holes for flow of air which keeps them comfortable and thus have a clear vision.
No. in case of welding work, appropriate welding shield, with proper shade, is the suitable solution. The wavelength of IR, emitted from different types of welding or cutting works, is much higher than the wave length of normal light.
Safety spectacles with smoked lens are suitable for working out-door. This smoked lens offers solar protection and the shade allows appropriate light transmission through it, thus making it suitable to wear out-door.
Since amber lens blocks some of the colours, thus enhancing the vision of objects surrounding you in the present low light. Amber lens are suitable to wear in cloudy conditions or dim lights. It cannot be used in absence of light.
No, Safety spectacles are not provided with photo-chromatic lens. Slight tint of coating is done over the lens to get the look.
If the lenses is slight-tinted coated, it allows to transmit a particular intensity of light in the situation, low light and high light. So by wearing this safety spectacle, the users feel comfortable to adapt to low light in floor shop and high light in outdoor works.
Udyogi INOX Indoor/Outdoor model is an ideal safety spectacle in this case.
No, Laser is a process where higher energy and heat are involved. Special spectacle with standards for laser protection should be used. Welding spectacles are not suitable for laser protection.
The safety spectacle goes through impact test keeping a range of temperatures-5°C to 55°C for one hour. The bare skin of a human being cannot bear temperatures beyond these. Working in radiant temperatures beyond range of temperatures -5°C to 55°C, appropriate body (PPE) suits should be worn. The letter T denotes that the spectacle has been treated at extremes of temperature (-5°C for 1 hour and +55°C for 1 hour) before the impact test. It is advisable to wear safety spectacle with T marking in extreme temperature.
The life of safety spectacle is variable and it depends according to the usage and maintenance. The quality of coatings also becomes an important factor. Depending on the coating, the life varies from 1 month to 3 months. The working conditions also affect the life of the spectacle.
The certifying body ensures the quality of safety spectacle. They usually carry on necessary tests and certify the safety spectacles. The popular certifications in India are the ISI, ANSI and EN certifications. The tests are carried on the safety spectacle depending on the type application and hazards exposed. The respective markings will be embossed on the spectacle permanently. Since the lens and temple have different roles to play. These markings are done according to the tests the spectacle has undergone based on the respective standards.