Human Factors Flashcards
In the SHELL model, what 4 factors does liveware interact with?
Liveware
Software
Hardware
Environment
What does Boyle’s Law state?
Volume inversely proportional to Pressure
What does Charles’ Law state?
Volume proportional to Temperature (at constant Pressure)
What does Dalton’s Law state?
Overall Pressure = sum of partial pressures
What does Henry’s law state?
Amount of gas dissolved into a liquid is proportional to the pressure of the gas over the liquid
What does Fick’s law state?
Gas will diffuse from areas of high concentration to areas of low concentration
Where specifically does gas transfer take place?
Alveoli
What is the approximate value for total lung capacity?
6000ml
What is the approximate tidal lung capacity at rest?
500ml
Lung capacity - what constitutes vital capacity?
Resting tidal volume, Inspiratory reserve volume, expiratory reserve volume,
Lung capacity - what constitutes inspiratory capacity?
Resting tidal volume, inspiratory reserve volume
Lung capacity - what constitutes functional residual capacity?
Expiratory reserve volume, residual volume
How is oxygen carried around the body?
As oxyhaemoglobin in the corpuscles (red blood cells)
How is carbon dioxide transferred around the body?
Dissolved in the blood plasma as carbonic acid
What is increased rate of breathing usually triggered by?
Excess carbon dioxide in the blood reacting with the nervous system
How does carbon monoxide effect the body?
Bonds with haemoglobin more effectively than oxygen does so not enough oxygen is carried in the blood
What are the symptoms of carbon monoxide poisoning?
bright red blood so flushed appearance, headache, breathlessness, unconsciousness
How is carbon monoxide poisoning treated?
100% oxygen
What are the main artery and main vein called?
Aorta
Vena Cava
What do the coronary arteries do?
Supply the heart with blood
What is the cardiac output (litres per minute) for an adult at rest?
5 litres a minute
What is systolic and diastolic blood pressure.
systolic- arterial pressure when ventricles contract
diastolic- arterial pressure between beats when heart relaxed
Typical values for blood pressure in a young adult
120/80
What is the percentage and partial pressure of oxygen in the lungs at sea level
14.5% 100mmHg
At what altitude is the partial pressure of oxygen in the lungs half of that at sea level?
18000ft
What is the maximum height you should operate at without supplementary oxygen
10000ft
At what height is 100% oxygen and pressure breathing required?
40000
What is the time of useful consciousness when exposed to hypoxia at 25000ft when moderately active
2.5minutes
How much positive G can the body tolerate unaided?
7 to 8G
In terms of accelerations, what constitutes long duration?
> 1second
