In this module
Objectives covered: LO 1.4.1. By the end you will be able to:
- Name the main hazards to the eyes and face.
- Choose between safety glasses, goggles, face shields and welding helmets.
- Read Z87 and EN 166 markings and pick a welding filter shade.
- Know what to do after a chemical splash to the eye.
4.1 Hazards to the eyes and face
- Impact: chips and particles from grinding, chipping, drilling, hammering, cutting wire.
- Chemical: splashes of acids, alkalis (caustic soda), hydrogen peroxide, solvents and dye liquors.
- Dust: cement, cotton fly, sawdust, abrasive blasting.
- Heat: molten metal, hot slag, sparks, furnace openings.
- Optical radiation: arc welding, gas cutting, lasers and strong UV.
4.2 Types of eye and face protection
| Type | Protects against | Notes |
|---|---|---|
| Safety glasses with side shields | Flying particles from the front and side | OSHA 1910.133(a)(2) requires side protection where there are flying objects |
| Direct-vent goggles | Impact and large particles | Not for liquids or fine dust |
| Indirect-vent goggles | Chemical splash, dust | Choose anti-fog lenses for hot, humid areas |
| Non-vented goggles | Gases, vapours, fine mist | Fog quickly; use for short tasks |
| Face shield | Splash, sparks, heat to the whole face | A secondary protector: always wear glasses or goggles under it |
| Welding helmet or hand shield | Arc radiation, spatter | Wear safety glasses underneath for chipping slag |
A face shield alone is not eye protection. When the shield is lifted, the eyes are exposed. Always wear safety glasses or goggles under it.
4.3 Reading the markings
- OSHA 29 CFR 1910.133: eye and face protection in general industry.
- ANSI/ISEA Z87.1 (USA): Z87 = basic impact; Z87+ = high impact; D3 = splash or droplet; D4 = dust; D5 = fine dust; W plus a number = welding shade.
- EN 166 (Europe): mechanical strength S, F, B, A (increasing); field of use 3 = liquids, 4 = coarse dust, 5 = gas and fine dust, 9 = molten metal.
Workers who wear prescription glasses need either safety glasses made to their prescription, or goggles designed to fit over their own glasses (1910.133(a)(3)). Ordinary glasses are not safety glasses.
4.4 Welding filter shades
The higher the shade number, the darker the filter. OSHA 1910.133(a)(5) gives the minimum shade. Start darker and go lighter only if you cannot see the weld pool.
| Operation | Arc current | Minimum shade |
|---|---|---|
| Shielded metal arc (stick) welding | Less than 60 A | 7 |
| Shielded metal arc (stick) welding | 60 to 160 A | 8 |
| Shielded metal arc (stick) welding | 160 to 250 A | 10 |
| Shielded metal arc (stick) welding | 250 to 550 A | 11 |
| Gas welding, light (plate under 3 mm) | n/a | 4 |
| Oxygen cutting, light (plate under 25 mm) | n/a | 3 |
| Torch brazing | n/a | 3 |
Helpers and people nearby also need protection. Use welding screens around the work, and give helpers suitable shaded glasses.
4.5 First aid for eye splashes
Where corrosive chemicals are used, OSHA 1910.151(c) requires facilities for quick drenching or flushing of the eyes. ANSI Z358.1 sets good practice: an eyewash station within about 10 seconds' walk of the hazard, on the same level, with tepid water, able to flush for at least 15 minutes. Test it weekly.
- Go straight to the eyewash. Ask for help.
- Hold the eyelids open and flush for at least 15 minutes.
- Remove contact lenses while flushing if they come out easily.
- Get medical attention and take the SDS with you.
A dyeing operator was splashed with hot caustic soda solution while opening a sample port. The operator was wearing only safety glasses, and liquid ran in from the top. The factory moved to indirect-vent anti-fog goggles plus a face shield for all chemical sampling, installed a plumbed eyewash next to each machine row, and added a weekly test log. Cement grinding mills in Sylhet and Chattogram follow a similar approach for clinker dust, with sealed goggles marked for dust.
Learning Check
Answer these two questions to check your understanding. You can try again as many times as you like.