Chapter 6 - Physical Hazards

Question 1

Defintion

Answer 1

hazards that result from the transfer of energy

Question 2

Types of Hazards

Answer 2

noise, vibration, excess temperature, ionizing/non ionizing radiation, excess pressure

Question 3

Noise - how and where, parameters, health effects, instruments, OSHA standard ACGIH TLV (exchange rates)

Answer 3

unwanted sound (vibratory motion of displaced molecules in elastic medium). anatomy, sound generation (piston), sound parameters (amplitude and frequency), sound pressure and decibel, loudness (subjective), sound pressure weighting (approximate loudness at different frequencies A high, C low),

health effects - hearing loss (conductive i.e., interference, sensorineural), chronic exposure leads to notching, leads to stress and safety issues,

instruments - sound level meter, octave band analyzer, noise dosimeter,

OELs - based on continuous noise, intermittent noise, impact-type/impulsive noise, 5 dB exchange rate isn’t enough given inverse square law, OSHA range is 90 (8 hrs) to 115 (0.25hr) ACGIH is less uses 3 db exc

Noise pollition is #1 community quality of life complaint, health property value. few standards hard to enforce

Question 4

Vibration - how, types, common sources, health effects, parameters, instruments

Answer 4

mechanical interaction - either hand am vibration, whole body vibration

health effects: hand-arm (vibration white-finger, neuorological , carpal tunnel, muscular), whole body (damage to spine [back])

instruments - accelerometer

OSHA uses general duty clause, ACGIH has values based on acceleration (4-12 max)

Question 5

Extreme Temp - health effects, thermoregulation, parameters

Answer 5

heat stress thermoregulation (body is much better at dealing with warm temps than cold), heat production (basal metabolic heat), thermal exchange (evaporation, convection, conduction, radiation)

factors: controllable vs uncontrollable, insulation permeability ventilation , windchill for cold

health effects: heat stroke, heat exhaustion, heat rash heat cramps, fatigue. you have to maitain the thermal balance, cold : dexterity, hypothermia, frostbite, clothing properties

instruments - wet bulb globe temperature. combines air temp, humidity, air velocity, radiation (adjustment to temp based on clothing.

Question 6

Extreme Pressue

Answer 6

hypobaric (low pressure) hazards, hyperbaric (high pressure) changes in pressure mostly (decreases from high to low pressue)

Question 7

Radiation - types, health effects, instruments

Answer 7

ionizing (electron release, high frequency) nonionizing (vibration, low frequency), exposure is amt in air, dose is amt in tissue, half life, activity is decay rate. alpha, beta, neutrons, gamma xrays

health effects; ionization can damage DNA, leading to cell death or malignant DNA modification, nonionizing is heat generation (cell phones) resonance that allows ions through cell membranes. also optical radiation

instruments - activity rate meters (ionization chambers, geiger mueller counters, scintillation counters) personal dosimeters (film badge, pocket dosimeter, luminescent dosimeters, electronic dosimeters)