Physical Factors - Komura Flashcards
What are the four mechanical physical factors?
Motor vehicle accidents
Residence-related accidents
Work-related accidents
Disasters
What is significant about motor vehicle accidents?
They are the leading cause of accidental deaths
What are three pertinent facts about residence-related accidents?
- Accidental falls is the second leading cause of accidental deaths
- accidental drowning is the fourth leading cause of accidental deaths
- other important types: open flames, hot surfaces and liquids, medicines, sharp edges, electricity, lawn mowers
What are two pertinent facts about work-related accidents?
- accidents caused by fire and explosion of combustible material is the third leading cause of accidental deaths
- other important types: chemical burns, exposure to toxic gases, unsafe operation of machinery
Why do we consider disasters as environmental health specialists?
While natural disasters cannot be prevented, proper land use planning can mitigate their damage
Ex: earthquake, avalanche, rockslides, mudslides, flooding, wildfire
What is the equation for the measurement of sound in L Loudness?
dB = 20 log(P/Po)
dB is decibels
P is the given sound pressure
Po is the sound pressure of minimum audible sound
What do logarithms provide in the measurement of sound?
Permit the use of manageable numbers
Give a breakdown of the dB rating of noise on a scale of 0-120
0 - threshold of hearing
30 - very quiet (library)
60 - intrusive (conversation)
90 - very annoying (power lawnmower)
120 - maximum vocal effort (jet aircraft flyover)
When does hearing damage occur at 90 decibels?
after 8 hours
What is another factor measured when considering noise aside from decibels?
Frequency
Not all frequencies are detectable by the human ear, but it is still measured as noise
Noise from a point source does what in regards to distance?
Decreases according to the inverse square law
What does doubling sound pressure result in?
An increase in 3 dB
What does doubling distance of a noise point source results in?
A reduction of 6 dB
What are the physiological effects of noise?
Loss of hearing
instantaneous rupture of eardrum
chronic with continuous exposure to noise levels of 90 dB
What are the psychological effects of noise?
Invasion of privacy may trigger anger, tension, fear, and anxiety
What are the three main sources of noise?
- vehicles
- workplace machinery
- residence - stereos, aircraft, vehicles, machinery
What are the three types of ionizing radiation?
Alpha radiation
Beta radiation
X-rays
What are the characteristics of Alpha radiation?
low penetration (will not penetrate the skin)
more significant as an internal emitter
What are the characteristics of Beta radiation?
penetrate more than alpha
have internal and external emitter significance
What are the characteristics of X-rays?
highly penetrating
important external hazards
What are the four sources of ionizing radiation?
Earth
Solar
Cosmic
Man-made
Where does radiation from the earth come from?
coal contains radioactive material that is released when burned
Where does radiation from the sun come from?
Production of radioactive agents by cosmic radiation in the atmosphere
Where does man-made radiation come from?
Production of nuclear fuel
use of nuclear fuel
use of radioisotopes in industry, medicine, and research
Testing of nuclear weapons
