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Occupational Safety & Health for Technologists, Engineers, and Managers By David L. Goetsch

Chapter 21 - Radiation Hazards

Radiation Hazards

Chapter 21 – Section 13

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Occupational Safety & Health for Technologists, Engineers, and Managers By David L. Goetsch

Chapter 21 - Radiation Hazards

Radiation Hazards

Radiation hazards in the workplace fall into one of two categories:
ionizing
nonionizing

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Occupational Safety & Health for Technologists, Engineers, and Managers By David L. Goetsch

Chapter 21 - Radiation Hazards

IONIZING RADIATION: TERMS AND CONCEPTS

An ion is an electrically charged atom (or group of atoms) that becomes charged when a neutral atom (or group of atoms) loses or gains one or more electrons as a result of a chemical reaction.
If an electron is lost during this process—a positively charged ion is produced.
If an electron is gained—a negatively charged ion is produced.

To ionize is to become electrically charged or to change into ions.
Ionizing radiation is radiation that becomes electrically charged or changed into ions.

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Occupational Safety & Health for Technologists, Engineers, and Managers By David L. Goetsch

Chapter 21 - Radiation Hazards

IONIZING RADIATION: TERMS AND CONCEPTS

TYPES OF IONIZING RADIATION

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Occupational Safety & Health for Technologists, Engineers, and Managers By David L. Goetsch

Chapter 21 - Radiation Hazards

IONIZING RADIATION: TERMS AND CONCEPTS

OSHA CFR 1910.1096 - Basic terms and concepts:
Radiation - energetic nuclear particles.
Alpha, beta, gamma rays & X-rays.
Neutrons, high-speed electrons, and high-speed protons.
Radioactive material - material that emits corpuscular or electromagnetic emanations.
As the result of spontaneous nuclear disintegration.
Restricted area - any area to which access is restricted
in an attempt to protect employees from exposure to radiation or radioactive materials.
An unrestricted area is any area to which access is not controlled because there is no radioactivity hazard present.

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Occupational Safety & Health for Technologists, Engineers, and Managers By David L. Goetsch

Chapter 21 - Radiation Hazards

IONIZING RADIATION: TERMS AND CONCEPTS

OSHA CFR 1910.1096 - Basic terms and concepts:

A dose is the amount of ionizing radiation absorbed per unit of mass by part of the body or the whole body.

Rad - measure of the dose of ionizing radiation absorbed by body tissues stated in terms of the amount of energy absorbed per unit of mass of tissue.
One rad equals the absorption of 100 ergs per gram of tissue.
Rem - measure of the dose of ionizing radiation to body tissue stated in terms of its estimated biological effect relative to a dose of 1 roentgen (r) of X-rays.
Air dose - means that an instrument measures the air at or near the surface of the body where the highest dosage occurs to determine the level of the dose.

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Occupational Safety & Health for Technologists, Engineers, and Managers By David L. Goetsch

Chapter 21 - Radiation Hazards

IONIZING RADIATION: TERMS AND CONCEPTS

OSHA CFR 1910.1096 - Basic terms and concepts:

Personal monitoring devices are devices worn or carried by an individual to measure radiation doses received.
Widely used devices include film badges, pocket chambers, pocket dosimeters, and film rings.

A radiation area - any accessible area in which radiation hazards exist that could deliver doses as follows:
Within one hour, a major portion of the body could receive
more than 5 millirems.
Within five consecutive days, a major portion of the body
could receive more than 100 millirems.
A high-radiation area - any accessible area, in which radiation hazards exist, that could deliver a dose in
excess of 100 millirems within one hour.

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Occupational Safety & Health for Technologists, Engineers, and Managers By David L. Goetsch

Chapter 21 - Radiation Hazards

EXPOSURE OF EMPLOYEES TO RADIATION

Maximum doses for individuals
in one calendar quarter.

Employers are responsible for ensuring
that these dosages are not exceeded.

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Occupational Safety & Health for Technologists, Engineers, and Managers By David L. Goetsch

Chapter 21 - Radiation Hazards

EXPOSURE OF EMPLOYEES TO RADIATION

Nuclear Regulatory Commission (NRC) regulations specify total internal & external dose for employees may not exceed 5 rems per year.
This same revision established a total exposure limit of
0.6 rem over the entire course of a pregnancy for female employees.
According to the NRC, the average radiation exposure of nuclear plant workers is less than 400 millirems annually.

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Occupational Safety & Health for Technologists, Engineers, and Managers By David L. Goetsch

Chapter 21 - Radiation Hazards

PRECAUTIONS AND PERSONAL MONITORING

OSHA requires personal monitoring precautions for employees of companies that produce, use, release, dispose of, or store sources of ionizing radiation.
Employers must conduct comprehensive surveys to identify/evaluate radiation hazards in the workplace.
Employers must provide personal monitoring devices such as film badges, pocket chambers/dosimeters & film rings.

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Occupational Safety & Health for Technologists, Engineers, and Managers By David L. Goetsch

Chapter 21 - Radiation Hazards

PRECAUTIONS AND PERSONAL MONITORING

Employers must require the use of appropriate personal monitoring devices by the following:
Any employee who enters a restricted area where he/she is likely to receive a dose greater than 25% of the total limit of exposure specified for a calendar quarter.
Any employee 18 years of age or less who enters a restricted area where he/she is likely to receive a dose greater than 5% of the total limit of exposure specified
for a calendar quarter.
Any employee who enters a high-radiation area.

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Occupational Safety & Health for Technologists, Engineers, and Managers By David L. Goetsch

Chapter 21 - Radiation Hazards

CAUTION SIGNS AND LABELS

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The universal color
scheme for caution
signs/labels warning
of radiation hazards
is purple or magenta
superimposed on a
yellow background.

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Occupational Safety & Health for Technologists, Engineers, and Managers By David L. Goetsch

Chapter 21 - Radiation Hazards

CAUTION SIGNS AND LABELS

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OSHA & NRC require caution signs in radiation areas, high-radiation areas, airborne radiation areas, areas which contain radioactive materials,
and containers in which radioactive materials are stored or transported.

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Occupational Safety & Health for Technologists, Engineers, and Managers By David L. Goetsch

Chapter 21 - Radiation Hazards

CAUTION SIGNS AND LABELS

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On containers, the label should also include the quantity of radioactive material, kinds of radio-active materials & date
on which the contents
were measured.

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Occupational Safety & Health for Technologists, Engineers, and Managers By David L. Goetsch

Chapter 21 - Radiation Hazards

EVACUATION WARNING SIGNAL

Companies that produce, use, store, or transport radioactive materials are required to have a signal-system that can warn of the need for evacuation.

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Occupational Safety & Health for Technologists, Engineers, and Managers By David L. Goetsch

Chapter 21 - Radiation Hazards

EVACUATION WARNING SIGNAL

OSHA describes the signal system as:
…a mid-frequency complex sound wave amplitude modulated at a subsonic frequency.”
…not be less than 75 decibels at every location where
an individual may be present whose immediate, rapid,
and complete evacuation is essential.
…a sufficient number of signal generators must be installed to cover all personnel…
…unique, unduplicated, and instantly recognizable…
…long enough in duration to ensure that all potentially affected employees are able to hear it.
…the signal generator must respond automatically without the need for human activation ….fitted with backup power.

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Occupational Safety & Health for Technologists, Engineers, and Managers By David L. Goetsch

Chapter 21 - Radiation Hazards

INSTRUCTING AND INFORMING PERSONNEL

OSHA has established specific requirements for companies to keep employees informed concerning radiation hazards & precautions for minimizing them.
All employees must be informed of existing radiation hazards and where they exist.
The extent of the hazards, and how to protect themselves.
All employees must be advised of any reports of radiation exposure requested by other employees.
All employees must have ready access to 29 CFR 1910.1096 and related company operating procedures.

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Occupational Safety & Health for Technologists, Engineers, and Managers By David L. Goetsch

Chapter 21 - Radiation Hazards

STORAGE/DISPOSAL OF RADIOACTIVE MATERIAL

To preclude handling & transport, intentional or inadvertent, of radioactive materials by persons not qualified to move them safely, radioactive materials stored in unrestricted areas…
“…shall be secured against unauthorized removal from
the place of storage.”
A danger inherent in storing radioactive materials is that an employee, may unwittingly attempt to move the container and damage it in the process.
This could release doses that exceed prescribed acceptable limits.

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Occupational Safety & Health for Technologists, Engineers, and Managers By David L. Goetsch

Chapter 21 - Radiation Hazards

STORAGE/DISPOSAL OF RADIOACTIVE MATERIAL

There are only three acceptable ways to dispose
of radioactive waste:
Transfer to an authorized recipient
Transfer in a manner approved by the Atomic Energy Commission.
Transfer in a manner approved by any state that has an agreement with the Atomic Energy Commission pursuant to Section 27(b) 42 U.S.C.

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Occupational Safety & Health for Technologists, Engineers, and Managers By David L. Goetsch

Chapter 21 - Radiation Hazards

NOTIFICATION OF INCIDENTS

An incident is defined by OSHA as follows

Exposure of the whole body of any individual to 25 rems
or more of radiation.
Exposure of the skin of the whole body of any individual
to 150 rems or more of radiation;
Or exposure of feet/ankles/hands/forearms to 375 rems or more.
Release of radioactive material in concentrations which,
if averaged over a period of 24 hours, would exceed
5,000 times the limit specified.
If an incident meeting one of these criteria occurs, the employer must notify the proper authorities immediately.

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Occupational Safety & Health for Technologists, Engineers, and Managers By David L. Goetsch

Chapter 21 - Radiation Hazards

NOTIFICATION OF INCIDENTS

Companies regulated by the AEC are to notify the commission—all other companies are to notify the U.S. assistant secretary of labor.
Telephone or telegraph notifications are sufficient to
satisfy the immediacy requirement.

Notification requirements are eased to 24 hours…
Where whole-body exposure is between 5 and 24 rems.
Exposure of the skin of the whole body is between 30
and 149 rems.
Exposure of feet/ankles/hands/forearms is between 75
and 374 rems.
Employers are required to follow up with a written report within 30 days.

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Occupational Safety & Health for Technologists, Engineers, and Managers By David L. Goetsch

Chapter 21 - Radiation Hazards

REPORTS AND RECORDS OF OVEREXPOSURE

When a report is filed concerning overexposure of an employee, it should be given to the employee.
Records should contain cumulative doses for each monitored employee.

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Occupational Safety & Health for Technologists, Engineers, and Managers By David L. Goetsch

Chapter 21 - Radiation Hazards

NOTICE TO EMPLOYEES

The U.S. Nuclear Regulatory Commission (NRC) publishes NRC Form 3 to inform employees of the standards for protection against radiation.
What is the Nuclear Regulatory Commission?
An independent federal regulatory agency responsible for licensing and inspecting nuclear power plants and other commercial uses of radioactive materials.
What does the NRC do?
NRC’s primary responsibility is to ensure that workers and the public are protected from unnecessary or excessive exposure to radiation and that nuclear facilities,are constructed to high-quality standards & operated in a safe manner.

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Occupational Safety & Health for Technologists, Engineers, and Managers By David L. Goetsch

Chapter 21 - Radiation Hazards

NOTICE TO EMPLOYEES

The U.S. Nuclear Regulatory Commission (NRC) publishes NRC Form 3 to inform employees of the standards for protection against radiation.

What responsibility does my employer have?
Any company that conducts activities licensed by the
NRC must comply with the NRC’s requirements.

What is my responsibility?
For your protection & that of your coworkers, you should know how NRC requirements relate to your work, and obey them.
What if I cause a violation?
If you engage in misconduct that may cause a violation of NRC requirements or would have caused a violation if not detected, or provided inaccurate/incomplete information to the NRC or your employer, you may be subject to enforcement action.

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Occupational Safety & Health for Technologists, Engineers, and Managers By David L. Goetsch

Chapter 21 - Radiation Hazards

NOTICE TO EMPLOYEES

The U.S. Nuclear Regulatory Commission (NRC) publishes NRC Form 3 to inform employees of the standards for protection against radiation.

How do I report violations and safety concerns?
If you believe that violations of NRC rules or the terms of the license have occurred, or if you have a safety concern, you should report them immediately to your supervisor.
You may report violations/safety concerns directly to the NRC.

What if I work with radioactive material or in the vicinity
of a radioactive source?
If you work with radioactive materials or near a radiation
source, the amount of radiation exposure that you are
permitted to receive may be limited by NRC regulations.

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Occupational Safety & Health for Technologists, Engineers, and Managers By David L. Goetsch

Chapter 21 - Radiation Hazards

NOTICE TO EMPLOYEES

The U.S. Nuclear Regulatory Commission (NRC) publishes NRC Form 3 to inform employees of the standards for protection against radiation.

May I get a record of my radiation exposure?
Yes. Your employer is required to advise you of your dose annually if you are exposed to radiation for which monitoring was required by NRC.

How are violations of NRC requirements identified?
NRC conducts regular inspections at licensed facilities to assure compliance with NRC requirements.
May I talk with an NRC inspector?
Yes. NRC inspectors want to talk to you if you are worried about radiation safety or have other safety concerns about licensed activities.

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Occupational Safety & Health for Technologists, Engineers, and Managers By David L. Goetsch

Chapter 21 - Radiation Hazards

NOTICE TO EMPLOYEES

The U.S. Nuclear Regulatory Commission (NRC) publishes NRC Form 3 to inform employees of the standards for protection against radiation.

May I request an inspection?
Yes. If you believe that your employer has not corrected violations involving radiological working conditions, you
may request an inspection.

How do I contact the NRC?
Talk to an NRC inspector on-site, or call or write to the
nearest NRC Regional Office in your geographical area.
Can I be fired for raising a safety concern?
Federal law prohibits an employer from firing or otherwise discriminating against you for bringing safety concerns to the attention of your employer or the NRC.

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Occupational Safety & Health for Technologists, Engineers, and Managers By David L. Goetsch

Chapter 21 - Radiation Hazards

NONIONIZING RADIATION

Nonionizing radiation has a frequency (hertz, cycles per second) of 1015 or less, and a wavelength in meters of 3 Hz 10-7 or less.
Visible, ultraviolet, infrared, microwave, radio & AC power.

Radiation at these frequency levels does not have sufficient energy to shatter atoms and ionize them.
However, such radiation can cause blisters and blindness.
There is mounting evidence of a link between nonionizing radiation and cancer.

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Occupational Safety & Health for Technologists, Engineers, and Managers By David L. Goetsch

Chapter 21 - Radiation Hazards

NONIONIZING RADIATION

The warning symbol for radio frequency radiation.

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Occupational Safety & Health for Technologists, Engineers, and Managers By David L. Goetsch

Chapter 21 - Radiation Hazards

NONIONIZING RADIATION

Visible radiation comes from light sources that create distortion, a hazard to employees whose
jobs require color perception.
8% of the male population is red color-blind and cannot properly perceive red warning signs..
The most common source of ultraviolet radiation is the sun—potential problems include sunburn, skin cancer, and cataracts.
Precautionary measures include special sunglasses treated to block ultraviolet rays, and protective clothing.
Other sources of ultraviolet radiation include lasers, welding arcs, and ultraviolet lamps.

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Occupational Safety & Health for Technologists, Engineers, and Managers By David L. Goetsch

Chapter 21 - Radiation Hazards

NONIONIZING RADIATION

Infrared radiation creates heat—problems involve heat stress and dry skin and eyes.
Primary sources of infrared radiation are high-temperature processes such as the production of glass and steel.

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Occupational Safety & Health for Technologists, Engineers, and Managers By David L. Goetsch

Chapter 21 - Radiation Hazards

NONIONIZING RADIATION

Radio frequency (RF) & microwave (MW) radiation are electromagnetic radiation in the frequency range of 3 kilohertz (kHz) to 300 gigahertz (GHz)
Microwaves occupy the spectral region between 300 GHz and 300 MHz & RF or radio waves are 300 MHz to 3 kHz.
RF and MW radiation are nonionizing in that there is insufficient energy to ionize biologically important atoms.
Primary health effects of RF and MW energy are considered to be thermal.
Absorption of RF and MW energy varies with frequency.
Microwave frequencies produce a skin effect—you can literally sense your skin starting to feel warm.
RF may penetrate the body & be absorbed in deep body organs without the skin effect that can warn an individual of danger.

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Occupational Safety & Health for Technologists, Engineers, and Managers By David L. Goetsch

Chapter 21 - Radiation Hazards

NONIONIZING RADIATION

Use of RF and MW radiation includes:
Aeronautical/citizen’s (CB) radios, cellular phones, radar.
Processing/cooking of foods, heat sealers.
Vinyl welders, high-frequency welders, induction heaters, flow solder machines.
Ion implant equipment, microwave drying equipment, sputtering equipment, glue curing, and power amplifiers.

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Occupational Safety & Health for Technologists, Engineers, and Managers By David L. Goetsch

Chapter 21 - Radiation Hazards

NONIONIZING RADIATION

Extremely low frequency (ELF) radiation includes alternating current (AC) fields & nonionizing radiation from 1 Hz to 300 Hz.
As ELF frequencies are low (on the order of 1,000 km wavelengths), static electromagnetic fields are created.
ELF fields are considered as separate, independent, nonradiating electric and magnetic fields.
Electric and magnetic fields (EMFs) at 60 Hz are produced by power lines, electrical wiring, and electrical equipment.
Electric fields are produced by voltage and increase in strength as the voltage increases.
Measured in units of volts per meter (V/m).

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Occupational Safety & Health for Technologists, Engineers, and Managers By David L. Goetsch

Chapter 21 - Radiation Hazards

NONIONIZING RADIATION

Magnetic fields are from the flow of current through wires or electrical devices and increase in strength as the current increases.
Magnetic fields are measured in gauss (G) or tesla (T).
Electrical equipment usually must be turned on for
a magnetic field to be produced.
Electric fields are present even when equipment is
turned off, as long as it is plugged in.
Exposure to EMFs depends on the strength of the magnetic field sources, the distance from those sources, and the time spent in the magnetic field.

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Occupational Safety & Health for Technologists, Engineers, and Managers By David L. Goetsch

Chapter 21 - Radiation Hazards

NONIONIZING RADIATION

Hazards of lasers consist of a thermal threat to the eyes and of electrocution from power sources.
Smoke created by lasers in some processes can be toxic.

Video display terminals (VDTs) emit various kinds
of nonionizing radiation—typically, levels are well below established standards.
Concerns persist about the long-term effects of prolonged and continual exposure to VDT-based radiation.

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Occupational Safety & Health for Technologists, Engineers, and Managers By David L. Goetsch

Chapter 21 - Radiation Hazards

ELECTROMAGNETIC FIELDS IN THE WORKPLACE

Studies of potential effects on worker health of occupational exposure to electric & magnetic fields reported a variety of subjective complaints, including problems with their cardiovascular, digestive, and central nervous systems.
While much of the research has been inconclusive, the case for a clear link between EMFs and a variety of health problems is strong.

The health problems most frequently associated with EMF exposure are brain cancer, acute myeloid leukemia, leukemia, and lymphatic leukemia

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Occupational Safety & Health for Technologists, Engineers, and Managers By David L. Goetsch

Chapter 21 - Radiation Hazards

ELECTROMAGNETIC FIELDS IN THE WORKPLACE

Occupations with a higher-than-normal incidence of leukemia and brain cancer:
Telephone operators; Electrical manufacturing workers.
Power plant workers; Electrical engineers & line workers.
Power station operators; Electricians & cable splicers.

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Occupational Safety & Health for Technologists, Engineers, and Managers By David L. Goetsch

Chapter 21 - Radiation Hazards

Cancellation Approach

Cancellation is an attenuation technique in which the magnetic fields produced by sources of electricity are, in effect, canceled out.
Phase currents flowing through a given conductor are canceled out or drastically reduced by phase currents flowing in the opposite conductors.

In many cases, a principal source of magnetic fields is found to be the conductor systems leading to tools or power apparatus.
These fields could be canceled via compaction of the conductor systems.

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Occupational Safety & Health for Technologists, Engineers, and Managers By David L. Goetsch

Chapter 21 - Radiation Hazards

Shielding Approach

Shielding, another approach to decrease exposure to EMFs, requires the magnetic fields to be diverted around the volume considered to be sensitive to the magnetic fields, or to be contained within the device that produces the fields.
Effectively accomplishing shielding at either the source
or the subject requires extreme care in choosing the shielding material.
Both cancellation and shielding are highly technical approaches requiring specialized knowledge.
It may be necessary to consult with EMF experts before attempting to implement either approach.