Ice Rescuer Flashcards
What causes booming sound on ice on cold days?
Ice sheets expanding and changing shape with the change in air temp
How much weaker is river ice compared to lake ice?
15%
How do chemicals and pollutants affect water chemistry during ice formation?
Causes melting and interferes with strong ice formation
What is vasoconstriction?
Body cools and extremities squeeze blood to the core.
Water will rob the body of heat how many times faster than air?
20
What three parts of body does heat escape from the fastest?
Head/neck
Thorax
Groin
Vasoconstriction causes and increase of what?
Blood pressure
Explain the 1-10-1 rule.
3 phases of cold water immersion
1 minute to get breathing under control.
10 minutes for meaningful movement of extremities.
1 hour of consciousness
Frazzle ice
Stage one of ice formation; weak; looks like oil sheen
Pancake ice
Plates of ice that erode together rounding the edges.
Brash ice
Groups of broken off ice caused by weather or passing vessels
Difficult to judge strength
Clear ice
Strongest form of ice; color of water underneath; forms when cold and little wind
Snow ice
Milky; low density and porous; unpredictable
Ice fracture/crack
Small crack; can be opened or closed; weaker ice near crack
Ice lead
Large crack; greater than 3 feet
Polynya
Isolated pools of open water; caused by localized disturbances
Ice floe
Flat piece of ice 10ft or larger in diameter; caused by wind/currents
Fast ice
Ice attached to shore
Pack ice
Accumulation of floes packed together, can be unstable
Pressure ridge/windrow
Rows of piles of ice formed by wind; gets bigger over time
Rubble
Accumulation of windrows; very rough terrain
Candle ice
Looks like bundles of candles; found in spring when ice is deteriorating
Indicators of fluctuating water levels
Seepage from cracks
Lake levels
Flooding caused by ice jams
Lower water levels weaken ice
Signs of ice deterioration
Porous
Pools of water on top
Ice shifting or expanding
Effects of air temp
Ice expands and contracts with air temp changes
Booming sound is expanding ice
Effects of current
River ice is 15% weaker than lake ice
Currents erode ice from underneath
River mouths are dangerous
Four stages of hypothermia
1- mild
Awake&shivering; 90-95
2- moderate
Drowsy¬ shivering; 82-90
3- severe
Unconscious¬ shivering; 68-82
4- profound
No vital signs; less than 68
Required crew rest
10 hours in 24 hour period with 6 hrs continuous sleep
Fatigue standards
Thin ice, >30 KTS, < 10 deg = 4 hrs
Thick ice, 10 deg = 6 hrs
Avast
Arm up with closed fist
Wave light horizontally
One whistle
One pull
Ease
Wave arm up and down
Wave light vertically
Two whistles
Two pulls
Heave around
Arm up in circular motion
Light up in circular motion
Three whistles
Three pulls
Help
Waves both arms
Vigorously wave light
4 or more whistles
Four pulls
How to transit ice
10-15 feet apart
Pulley ratio for MARSARS
4:1
