Mask Squeeze is the condition that occurs due to incorrect equalization of the air pressure inside the mask causing the outside pressure at depth to push the scuba mask to a divers face resulting in bursting of the small blood vessels around the eyes.
Most of you have probably learned about Mask Squeeze during your Open Water certification, and probably never really paid too much attention to it as it didn’t seem that severe a condition. However mask squeeze is a severe diving trauma that shouldn’t be ignored.
The condition is caused when a diver fails to exhale into the mask during descent to equalize the pressure within the mask. Most divers will pay attention to equalizing their ears, but will often not even notice their scuba mask pressure increasing as they descend often not realizing the effects until after they surface.
Mask Squeeze can cause bruising around the eye, sub-conjunctival hemorrhage (blood spots over the white of the eye), and swelling. It rarely causes injury inside the eyeball; however, one can immediately spot the symptoms of mask squeeze by blood filled eyes. This type of hemorrhage isn’t dangerous, and the blood in the eyes should clear away in a couple of days, otherwise a Diver should seek medical help. If there is any loss of vision or pain, one should visit a doctor straight away. Often divers are greatly alarmed and panicky when they see blood in their eyes, but the condition isn’t as serious as it looks and in most cases clears away without any major treatment.
Factors that attribute towards mask squeeze apart from the Diver failing to exhale into the mask regularly to equalize pressure are: Poor dive mask fitting while purchasing scuba diving equipment. Often divers select a mask that is too tight to begin with, or too small for their face. A Scuba mask should sit comfortably on the divers face and stick when mild pressure is applied even without the strap being worn. Never have your masks on too tight to begin with, as once you descend, the pressure automatically causes an increased suction on the mask. Also choose a mask with ample silicone skirting that cushion and spreads the pressure around your face.
The other factor that contributes to mask squeeze is descending too fast. Often a diver in his haste to catch up with the group rapidly descends without regular equalization. Also the fear of getting water into the mask also results in divers not puffing air into their masks. We have seen this happen too many times, and this can only be remedied by a diver getting comfortable with taking off and putting on his/her mask underwater through practice. Modern dive masks have nose valves that allow divers to equalize the air space between their mask and face without the risk of the mask flooding with water, so divers who don’t like getting water in their eyes should opt for such masks.