Chapter 43

NON-IONIZING RADIATION

Contents

Approved by Robert Fairchild
Revised 11/16

43.1 Policy
43.2 Scope
43.3 Applicability
43.4 Exceptions
43.5 Roles and Responsibilities
43.6 Definitions
43.7 Required Work Processes

Work Process A. Non-ionizing Radiation Flowchart
Work Process B. Exposure Limits     
Work Process C. Methods of Exposure Control
Work Process D. Additional Information

43.8 Source Requirements
43.9 Reference Documents

NOTE:
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43.1 Policy

The Lawrence Berkeley National Laboratory (Berkeley Lab) Non-ionizing Radiation (NIR) Program is designed to provide a safe working environment for staff that ensures NIR exposure does not exceed the Threshold Limit Values (TLV) for the human eye or skin. The NIR Program at Berkeley Lab ensures personnel are protected from NIR exposure hazards including:

Note: Laser and acoustic (noise) exposures are covered in separate policies.

43.2 Scope

Non-ionizing Radiation (NIR) refers to electromagnetic radiation with insufficient energy to release a bound electron from an atom. NIR includes the following categories of radiation: ultraviolet (UV), visible light, infrared, radio frequency, microwave, and magnetic fields. (Lasers are covered in the Laser Safety Program.)

43.3 Applicability

This program applies to Berkeley Lab employees, casual and participating visitors, affiliates, and subcontractors who may perform work in or around NIR sources with the potential for an over exposure.

43.4 Exceptions

Laser work is covered by the Laser Safety Program.

43.5 Roles and Responsibilities

Role

Responsibilities

Division Director

Ensures the NIR Program is enforced

Environment, Health & Safety (EHS) Division

  • Arranges or performs NIR assessment as requested or determined by an approved activity within the Work Planning and Control (WPC) system or other authorization method
  • Establishes controls for NIR hazards
  • Maintains the Berkeley Lab NIR Program
  • Develops and reviews substitute or alternate control measures when primary measures are infeasible or impractical
  • With Activity Lead, investigates all instances of suspected exposure

Supervisor/
Activity Lead

 

  • Ensures that all NIR users receive adequate and appropriate training
  • Ensures that all NIR users are assigned to a WPC Activity
  • Prepares an Activity in WPC for an NIR operation and ensures that the provisions of the Activity are properly implemented and diligently followed by users. (To complete an Activity, go to the WPC link on the Berkeley Lab A–Z listing.)
  • Ensures that any visitor receives a site/experimental hazard orientation as part of any visit to any NIR area
  • Investigates all instances of suspected exposure

NIR Equipment Users

  • Receives appropriate on-the-job training (OJT) prior to unsupervised NIR equipment use
  • Reads, understands, signs, and follows all procedures in the WPC Activity
  • Stops unsafe work activities (see PUB-3000, Chapter 1, Work Process C, Stopping Unsafe Work)
  • Works in a safe manner following Laboratory policy and procedural requirements
  • Promptly reports any malfunctions, problems, accidents, or injuries that may have an impact on safety
  • Immediately reports any suspected NIR exposures to the  supervisor and EHS
  • Refers any questions or concerns to the NIR Subject Matter Expert

Important considerations for determining the full extent of safety control measures include:

43.6 Definitions

Term

Definition

Ultraviolet (UV) Radiation

Electromagnetic radiation greater than 10 nm but less than 400 nm

Visible light

Electromagnetic radiation greater than 400 nm but less than 700 nm

Infrared Radiation

Electromagnetic radiation greater than 700 nm but less than 1 mm

Radio Frequency Radiation

Electromagnetic waves greater than 3 kHz but less than 300 GHz

Microwave Radiation

Electromagnetic waves greater than 300 MHz to 300 GHz (within RF frequencies)

NIR

Non-ionizing Radiation (NIR) refers to electromagnetic radiation with insufficient energy to release a bound electron from an atom. NIR includes the following categories of radiation: ultraviolet (UV), visible light, infrared, radio frequency, microwave, magnetic fields, and lasers.

Electromagnetic spectrum

http://bccp.lbl.gov/Academy/wksp_pix_1/spectrum.gif

43.7 Required Work Processes

Work Process A. Non-ionizing Radiation Flowchart
Work Process B. Exposure Limits     
Work Process C. Methods of Exposure Control
Work Process D. Additional Information

Work Process A. Non-ionizing Radiation Flowchart

CH43-NIR-flowchart.png

Work Process B. Exposure Limits

In accordance with 10CFR851, exposures to non-ionizing radiation must be below the limits specified in the 2005 version of Threshold Limit Values for Chemical Substances and Physical Agents, American Conference of Governmental Industrial Hygienists (ACGIH). Because the process to determine the threshold limit value (TLV) is complex and may be adjusted for likely exposure duration, only the most common limits for conditions expected to be encountered at LBNL are listed below. The TLVs for specific applications and exposure conditions may be obtained by contacting the non-ionizing radiation subject matter expert.

Light and Near-Infrared Radiation
TLVs for light and near-infrared radiation apply to incoherent (non-laser) sources of visible and near-infrared radiation. These limits are based on an 8-hour exposure. The TLV is application specific and must be calculated for any broadband light source with a luminance greater than 1 candela/cm2. Contact the non-ionizing radiation subject matter expert to determine the appropriate TLV for light sources with luminance greater than 1 candela/cm2.

Magnetic Fields
The TLVs for magnetic fields are divided into those limits that apply to static (DC) or (CW) magnetic fields and those that apply to sub-radiofrequency magnetic fields or alternating (AC) magnetic fields. The TLV for sub-radiofrequency magnetic fields are frequency specific.

The highest concern is for personnel who have implanted medical devices. Magnetic fields may disrupt the proper function of these devices and have catastrophic effects. This is not limited to cardiac pacemakers, but includes a wide range of devices, such as implantable cardioverter defibrillators (ICDs) and neurostimulators. The TLV in the table below is to be implemented for such devices unless specific higher values are provided in manufacturer-provided documentation.

TLV for Static Magnetic Fields

Exposure

TLV

Medical Device Wearers

5 Gauss (0.5 mT) max

Whole Body (general workplace)

20000 Gauss (2T) max

Whole Body (general workplace)

600 Gauss (60 mT) 8-hour average

Limbs

50000 Gauss (5T) max

Limbs

6000 Gauss (600 mT) 8-hour average

 

TLV for Sub-Radiofrequency Magnetic Fields

Exposure

Frequency

TLV

Medical Device Wearers

60 Hz

1 Gauss (0.1 mT) max

Whole Body (general workplace)
Arms and Legs
Hands and Feet

60 Hz

10 Gauss (1 mT) max
50 Gauss (5 mT)
100 Gauss (10 mT)

Whole Body (general workplace)
Arms and Legs
Hands and Feet

300 Hz to 30 kHz

2 Gauss (0.2 mT) max
2 Gauss (0.2 mT) max
2 Gauss (0.2 mT) max

Radiofrequency and Microwave Radiation
The TLVs for radiofrequency and microwave radiation are dependent on the frequency of the source. Limits apply to all sources from 1 Hz to 300 GHz and often include more than one limiting value, such as electric field strength (V/m), magnetic field strength (A/m), and limits on current induced within the human body (mA).

Part A – Electromagnetic Field TLV

Radiofrequency

Power Density,
S (W/m2)

Electric Field Strength,
E (V/m)

Magnetic Field Strength,
H (A/m)

Averaging Time E2, H2, or S
(minutes)

2.0 MHz

 

921

8.15

6

13.56 MHz

 

135

1.2

6

27.12 MHz

 

67.9

0.6

6

40 MHz

 

61.4

0.4

6

100 MHz

10

61.4

0.163

6

500 MHz

16.6

 

 

6

2.45 GHz

81.6

 

 

6

2.54 GHz

84.6

 

 

6

6.0 GHz

100

 

 

2.83

6.4 GHz

100

 

 

2.64

7.0 GHz

100

 

 

2.4

8.5 GHz

100

 

 

1.95

10 GHz

100

 

 

1.63

14 GHz

100

 

 

1.13

18 GHz

100

 

 

0.86

28 GHz

100

 

 

0.53

30 GHz

100

 

 

0.50

Note that in addition to the above electromagnetic field TLVs, induced and contact radiofrequency current TLVs also apply to radiofrequency radiation from 30 kHz to 100 MHz. See the table below for commonly encountered frequencies and their respective limits. The TLVs for specific applications and exposure conditions may be obtained by contacting the non-ionizing radiation subject matter expert.

Part B – Induced and Contact Radiofrequency Currents
Maximum Current

Radiofrequency

Through both feet

Through either foot

Grasping

Averaging Time

1 Hz – 2.5 kHz

1 mA

1 mA

1 mA

N/A

2.5 kHz – 100 kHz

variable

variable

variable

0.2 second

100 kHz – 100 MHz

200 mA

100 mA

100 mA

6 minutes

Ultraviolet (UV) Radiation
The TLVs for UV radiation apply to electromagnetic radiation with a wavelength between 180 nm and 400 nm. Such radiation may present an eye and skin hazard. These TLVs apply to UV radiation from plasma discharges (e.g., welding, plasma etchers, etc.), solar simulators, unfiltered fluorescent and incandescent lights, and other incoherent UV sources. These TLVs do not apply to UV lasers.

The TLVs for UV radiation are wavelength and time dependent. The TLVs listed in the table below are the most restrictive. Contact the non-ionizing radiation subject matter expert for an evaluation of specific UV hazards and determination of specific application TLVs if these limits cannot be met.


Incoherent UV Radiation TLVs

Duration of Exposure Per Day

Effective Irradiance Eeff (µW/cm2)

8 hours

0.1

4 hours

0.2

2 hours

0.4

1 hour

0.8

30 minutes

1.7

15 minutes

3.3

10 minutes

5

5 minutes

10

1 minutes

50

30 seconds

100

10 seconds

300

1 seconds

3000

0.5 seconds

6000

0.1 seconds

30000

Work Process C. Methods of Exposure Control

Where feasible, engineering controls are used to limit exposure to non-ionizing radiation. Otherwise, administrative controls and personal protective equipment are used.

Work Process D. Additional Information

For assistance with NIR, contact the EHS NIR Safety Coordinator, ext. 2544.

43.8 Source Requirement Documents

43.9 Reference Documents

Document number

Title

Type

07.02.003.001

Work Planning and Control 

Program

07.07.018.001

Laser Safety

Program

 

 

 

 

 

 

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