1. Limited Visibility Diving

2. A great deal of diving occurs in limited visibility. Limited visibility can make it difficult to achieve the objectives of the dive.

3. Main Topics Definition of limited visibility Causes of limited visibility Avoiding limited visibility Techniques for diving in limited visibility

4. Learning Objectives Define limited visibility List at least three causes of limited visibility Describe at least four techniques which should be employed during limited visibility diving.

5. Defintion Limited Visibility –Less than 10 feet

6. Causes lack of light –Turbidity (particulate matter in water) diver –poor buoyancy stirs up bottom –brushing against kelp stirs up mid-water wind –creates waves upwelling –plankton blooms tides –stirs up bottom currents –disturbs sediment runoff –creates turbidity pollution –creates turbidity

7. Avoidance Select appropriate time and site

8. Techniques Dive planning/pattern Buddy techniques Buoyancy control Navigation Dive lights Descent/ascent lines Tether lines –make sure it has a quick release Site orientation –local knowledge Minimum task loading

9. Main Topics Definition of limited visibility Causes of limited visibility Avoiding limited visibility Techniques for diving in limited visibility

10. Learning Objectives Define limited visibility List at least three causes of limited visibility Describe at least four techniques which should be employed during limited visibility diving.

11. Summary Proper planning along with strong dive skills and appropriate techniques can minimize the inconvenience of limited visibility, and increase the likelihood of achieving the dive objectives.