1. Masks

2. Safety Features Tempered glass lens Nose coverage –Allows you to equalize the pressure in your mask Wide or split strap Non-corrosive retaining band

3. Testing Mask Fit Proper fit is the most important consideration when selecting your mask***. Hold the mask against your face without using the strap. –Inhale lightly through your nose. –The mask should suck in against your face –No air should leak into the mask –The mask should remain sealed to your face for at least a few seconds after you stop inhaling through your nose

4. Mask Styles and Features Low volume vs. high volume Purge vs. non-purge Side windows vs. non-side windows Clear skirt material vs. non-clear Split lens vs. single lens Lens coatings Optical correction Frame vs. Frameless

5. Mask Volume Low Volume Often used in breath hold diving. Streamlined Less air to equalize or clear May offer smaller field of vision High volume Used more often in scuba More open May offer greater field of vision Less streamlined More air to equalize or clear

6. Single vs. Split Lens Single Lens Broad uninterrupted view Greater volume? Split Lens Lower volume

7. Side Windows vs. No Windows Side Windows Greater field of view Can be distracting No side window Focused field of view May feel confining

8. Skirt Material Clear skirt Very Bright Lens may act as mirror Black skirt Prevents effect My feel confining

9. Purge Hands free clearing May block access to nose May leak

10. Frameless Reduced weight Reduced volume Comfort

11. Lens Coatings UV protection Improve depth perception Define faint edges Maximize available light Restore: yellows, oranges, and reds Minimize glare

12. Optical Correction Soft contacts Standard corrective lenses Prescription masks

14. De-Fogging Techniques Scrub with toothpaste/TSP Defog Solutions –Commercial –Home Made Saliva

15. Objectives Identify the required safety features of a mask. Describe how to properly fit a mask to your face. Describe how to adjust your mask strap. Compare various styles of masks. Describe techniques for defogging your mask.