Flashcards in Bodies from Fire and Asphyxia Deck (59)
What is the incipient phase of fire dynamics?
Fuel supply heated and ready to burn
What happens in the emergent smouldering phase of fire dynamics?
What happens in growth flaming phase of fire dynamics?
Intensity doubles for each 10 degrees rise in temperature
What happens in the oxygen regulated smouldering phase of fire dynamics?
Free burning depletes available oxygen
Superheated gases and smoke
What are the 4 phases of fire dynamics?
2. Emergent smouldering
3. Growth flaming
4. Oxygen-related smouldering
What is the term for when a fire produces radiant heat and hot gases which brings nearby combustible objects to ignition temperature, then to ignite?
`What temperatures can flashovers produce?
What is the term for if the fires oxygen supply is depleted, flames die out, residual heat, gases and smouldering remains so reintroduction of oxygen to fire causes explosive ignition?
Name three primary identifiers for victims in fire?
DNA- need comparison sample
Name three secondary identigiers for victims of fire?
Medical devices and implants
Name some tertiary identifiers for victims of fire?
Circumstances, personal items, blood group and type
If victim was alive during fire what might be found on autopsy?
Soot creases around eyes
Soot around nostrils, mouth, airways
tehrmal injury to laryngeak mucosa
congestion of lungs
(CO and cyanide levels)
What czuses laryngeal injury?
Dry air bigger than 150 degrees. More common with steam inhalation (x4000 heat capacity of dry air)
What causes cardiac arrest with thermal airway injury?
Reflex vagal inhibition
What can cause tracheobronchial necrosis?
Thermal airway injury
What are normal levels of CO?
less than 1ppm- present in smokers and city dwellers
If CO bigger than 50% whast happens?
Fatalities- can be low as 30 in severe natural disease/children/elderly
What colour is carboxyhaemoglobin lividity?
Where will a 1-3 nm superheated soot particle reach?
Alveoli. Seen on histology.
What does cellulose, polyurethanes and acrylonitrile release?
What does PVC release?
What does burning wool, silk, nylons and polyurethanes release?
What does burning wool, cotton, paper, plasters, wood, nylon and polyester resin release?
What does burning petrol, plastics and polystyrene release?
What does burning melamine and nylon release?
Give an example of a radiany burn?
Sunburn- no direct contact
Describe a flash burn?
Uniform burning of exposed areas
What type of burn causes damage in less thsan one second for temperatures above 70?
What causes a scald?
Hot liquid or vapour