Difference Between a Snorkeling & Dive Mask

Seventy percent of the earth's surface is water, and with the proper equipment divers and snorkelers visit an environment that most people never see. Diving requires the use of specialized training and breathing equipment referred to as SCUBA -- Self Contained Underwater Breathing Apparatus. Snorkeling is done close to the water's surface and requires no certified training and less equipment. When planning a dive or snorkeling exploration, buy the best mask you can afford.

  1. The Importance of Masks

    • The human eye cannot focus underwater; without a mask the sea and its inhabitants are blurry and distorted and distant objects are indistinct at best. Snorkel and dive masks have an open airspace between the eyes and the glass of the mask. This airspace remains dry, providing the eyes with a window to look through. The "nose pocket" in a properly fitted mask should fit snugly over the nose; pressure in the ears is maintained by pinching the nose and exhaling. The smaller the airspace between the mask and the eyes, the less likely the mask will float off underwater.

    Purge vs. Non-Purge Masks

    • A mask with a purge is designed so the wearer can blow out water that has seeped into the airspace. A one-way valve in the nose pocket purges the water while the diver exhales through the nose without removing the mask. To clear water from a mask without a purge valve, the diver must hold the top of the mask while exhaling hard enough to force water out through the skirt or seal on the bottom of the mask. A purge valve on a snorkel mask is not necessary because the snorkeler can stand up or tread water while dumping water out of the mask.

    Materials

    • The material used to make the skirt that fits the mask tight to the face varies from one mask to another. Plastic skirts are stiff and dry out and crack quickly, but for a one-time surface snorkel session, an inexpensive plastic or neoprene skirt will suffice. Skirts made of silicone are useful for divers and serious snorkelers. Stores devoted to water sports sell silicone masks; big-box stores with less emphasis on underwater sports often sell plastic masks.

    Visibility

    • Dive and snorkeling masks are not effective unless the goggle portion is made of tempered glass. Plastic fogs easily underwater and regular glass can break into shards if damaged. Avoid darkly tinted lenses; they distort vision and may cause nausea. Divers who wear glasses or contact lenses can order prescription custom-made lenses. Masks with side windows offer better peripheral vision. Dive masks should have slanted lenses for maximum sight.

    Other Features

    • Select a dive mask with wide, easily adjustable straps and go with the smallest mask that fits to limit the amount of resistance caused by water. Snorkelers can easily readjust loose straps by standing up and tugging on them. Dive masks can have clear or black skirts; snorkel masks should have black skirts to limit the amount of light that comes through from the water's surface.