NonIonizing Radiation Flashcards
Nonionizing radiation often is not radiation but ____ or _____
electrical or magnetic fields
What is the frequency of nonionizing radiation?
number of times a field goes through a complete cycle of polarity
What is a wavelength in nonionizing radiation?
the distance traveled during one cycle
How are various frequencies of electric and magnetic fields divided?
the electromagnetic sectrum
What occupational standards are available for nonionizing radiation?
Limited OSHA standards, but consensus standards (from ACGIH) can be enforced
What is the relationship between frequency and energy level?
higher energy levels at higher frequencies
At higher energy levels we are concerned about ___, and at lower non-ionizing energy levels we are also concern about ___
radiation, fields
How are electric fields produced?
by electric charge differences (voltage)
How are magnetic fields produced?
By electrons moving (current)
Electric fields can be produced by a ___ ___ ___ that can ___ current
moving magnetic field, induce
Example of electric fields
Generators
___ and ___ of alternating current produce electric (E) and magnetic (H) fields
transmission, use
What is the SAR?
Specific absorption rate- dose rate at which energy is transferred to tissue, expressed in watts/ kg of tissue
quantity of energy transferred to tissue
specific absorption
What is the equation for specific absorption rate?
SAR = (energy/ mass) / time
What are types of non-ionizing radiation?
- sub radio frequency
- radio frequency and microwave
- Optical
- Special applications
What are the types of optical non-ionizing radiation?
- infrared
- visible
- ultraviolet
What are the types of special applications nonionizing radiation?
- lasers
- static magnets
What type of field can the body conduct well?
electric, does not conduct magnetic fields well
Which field is easier to measure? why?
magnetic fields- they are not perturbed by the body, whereas the body distorts electric fields
What are the health impacts of sub-radiofrequency nonionizing radiation?
- Static magnetic fields: nausea, headaches, metallic taste
- disruption of circadian rhythm
- pacemaker and other implant concerns
- disruption of calcium ions movement through cell membrane
What are static magnetic sources?
Projectiles - magnetic resonance
What are the health effects of radiofrequency & microwaves
- damage to lens of eyes, testes, and skin
- cataracts, facial burns, electric shock
- electric burns at high level exposure (ankles)
- Animal teratogenic effects
Why can radiofrquency and microwaves be dangerous?
human body acts as antenna
What is an important factor that impacts health outcomes from radiofrequency and microwaves?
orientation of the body
Give an example of radiofrquency and microwaves
RADAR- radio detection and ranging
What are the heath effects of infrared?
- heating effects
- skin erythema and burns
- skin pigmentation
- cornea/ iris/ lens (cataracts)
Health effects of Visible radiation
- computer screens- fatigue
- moving from one light level to another- safety risk
- pulsed light
- flash blindness
- trips and falls due to lighting issues *
What do we have that relate to visible lights relationship with safety and productivity
Industrial light standards- need adequate light levels for the task
What are sources of UV light?
Biosafety cabinet with a UVC light- interlocked, labeled
What are the different UV lengths from longest to shortest?
UVA, UVB, UC
What are the health impacts of UV A
photosensitivity
lens damage
What are the health impacts of UV B
conjuncitivitis photosensitivity skin cancer erythema skin aging
What are the health impacts of UV C?
photosensitivity
erythema
bacteriocidal
What does laser stand for?
light amplification by stimulated emission of radiation
How do lasers work?
photon excites atom of lasing medium- direct energy out in form of a beam of radiation. Light keeps strength over long distance
What does the wavelength of a laser depend on?
lasing medium and energy released, can e IR, Visible, or UV
What are examples of lasers
CO2 lasers (gas-IR beam) Ruby lasers- solid
What do the health effects of lasers depend on?
wavelength
What are the health effects of IR lasers?
damage to cornea
What are the health effects of visible wave lasers?
damage to retina, cornea, lens
What are the health effects of UV lasers?
damage to cornea, cause erythema
What are the hazard classes for lasers?
1- harmless to 4- very hazardous
At high energy levels, what health impact can lasers cause?
burns
Are pulsed lasers or continuous lasers more dangerous?
pulsed lasers
what are other issues/ risks with lasers?
- fire
- electrocution
- explosion
- toxic gases
- scattering of light
What is the measurement device for sub-radiofrequency ad microwaves?
magnetic and electric survey meters
What is the measurement device for RF and microwaves?
induced current meter or contact current meter
What is the measuring instrument for optical radiation?
photometers
radiometer
dosimeters
What are the controls for all non-ionizing radiation?
- decrease time
- increase distance
- shield
What are additional controls for sub-radiofrequency?
-grounding and cancelling
What are additional controls for RF and microwave?
-metal mesh barrier or PPE
What are additional controls for optical radiation?
filters for glasses
What is an additional control for UV?
sunscreen
What are additional controls for lasers?
- limit access
- interlocks
- beam enclosure
- beam stops
- labeling, alarms