Night Diving
Why Do It?
• Night diving allows you to see different
critters and or different behaviors.
• It is another form of limited visibility diving
and some divers find their first night dive
both exciting and spooky.
Learning Objectives
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Describe the ideal setting for a night dive.
Discuss night diving techniques, including the
importance of navigation during a night dive.
State the minimum number of lights each diver should
carry during a night dive, and explain why.
Demonstrate standard light signals, and discuss light
etiquette.
Discuss features to be considered when selecting a
dive light, including re-chargeable vs, non rechargeable batteries.
Main Points
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Ideal setting
Buddy techniques
Communications
Light etiquette
Navigation
Avoiding disorientation
Required equipment
Lighting concerns
Ideal Setting
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Familiar site
Favorable conditions
Boat
Buddy contact
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Good buddy techniques
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Positioning
Plan the dive and dive the plan
Personal identification lights
Separation plan
Communications
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Light signals
– OK
– Attention
– Distress
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Diver-to-diver
Diver-to-shore or boat
Light Etiquette
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If the light is in your hand, it should be
on.
Don't shine your light in your buddy's
eyes.
Don’t shine the light in your eyes.
Control the light during descent.
Navigation
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More important at night than during
daylight
– Surface
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Use compass and range lights
Make sure you can identify the exit point.
– Underwater
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Plan your pattern and stick to it.
Don’t try to cover too much area.
Disorientation
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Most significant problem
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bubble trail
descent/ascent line
buddy
bottom
kelp
Breathing
Water in mask
Required Equipment
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All standard gear for daylight diving plus
2 dive lights per diver
– Purpose of the second light?
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1 ID/marker light per diver.
Dive Lights:
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primary vs. backup
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purpose/function
beam pattern
ease of use
size
maintenance
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store with batteries out
lubricate "O" rings
store with pressure off "O" rings
filament most vulnerable when light is on
Rechargeable Batteries
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Batteries die suddenly (little warning)
One charge doesn't last as long as standard battery
Battery Memory:
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Batteries may swell during charging, to the point that
they won't fit in the light.
Batteries may spike when freshly charged.
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If you charge battery before it is completely drained, eventually
the battery won't hold a charge as long.
Turn light on and leave it on to take the edge off.
If the battery hasn’t been used in a while the first
charge won’t last as long as normal.
Personal ID lights
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Strobe lights
Chem/ID Lights:
– color code dive teams
– position for maximum visibility
Surface Lights
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Ranges
Float or boat marker light
Flashing
Dressing area
Be aware of background light
Have We Covered
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Ideal setting
Buddy techniques
Communications
Light etiquette
Navigation
Avoiding disorientation
Required equipment
Lighting concerns
Can You
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Describe the ideal setting for a night dive.
Discuss night diving techniques, including the
importance of navigation during a night dive.
State the minimum number of lights each diver should
carry during a night dive, and explain why.
Demonstrate standard light signals, and discuss light
etiquette.
Discuss features to be considered when selecting a
dive light, including re-chargeable vs, non rechargeable batteries.