# Presentation: 906577

## RF & Microwave Radiation Hazard Awareness

***NASA ***
***Wallops Flight Facility***

## RF Radiation

- Radiation- is energy transmitted through space in the form of electromagnetic waves or sub-atomic particles
- Sources:
- Radiofrequency (RF) Radiation, Microwaves
- Infrared, Visible, Ultraviolet Light
- X-rays and Gamma Rays

## RF Radiation

- The term “electromagnetic radiation” is restricted to that portion of the spectrum commonly defined as the radio frequency region, which for our purposes also includes the microwave frequency region.

## RF Radiation

- Hazards of Electromagnetic Radiation to Personnel (HERP)
- Hazards of Electromagnetic Radiation to Ordance (HERO)
- Electro Magnetic Interference (EMI)

## RF Radiation

- HERP (Effects only possible at ten times the permissible exposure limit)
- Heating of the body
- Cataracts
- Reduced sperm count in males
- Shocks or Burns
- (Developing fetus is at no greater risk than mother)

## RF Radiation

- HERO
- Premature activation of electroexplosive devices.
- EMI
- Interference with other electronic equipment

## RF Radiation

- Exposure limits are specific for locations that are defined as either controlled or uncontrolled environments.
- Controlled environments are areas where exposure may be incurred by personnel who are aware of the potential for RF exposure as a result of employment or duties; by individuals who knowingly enter areas where higher RF levels can reasonably be anticipated to exist; and by exposure incidental to transient passage through such areas.
- Uncontrolled environments generally include public areas, living quarters and work places where there is no expectation that higher RF levels should be encountered.

## RF Radiation Standards

- OSHA 29 CFR 1910.97 (a)(2)(i)
- For normal environmental conditions and for incident electromagnetic energy of frequencies from 10 MHz to 100 GHz, the radiation protection guide is 10 mW/cm2. (milliwatt per square centimeter) as _averaged_ over any possible 0.1 hour period (6 minute period)

## Standards

- OSHA 1910.268 - Telecommunication Industry
- Primarily safety requirements, such as electrical
- Mandates 1910.97 compliance for 1-300 GHz
- Describes “Tagout” of antenna 3-300 MHz
- OSHA 1926.54, 20 - Construction Industry
- Includes tower erection, repairs and painting
- Limits MW to 10 mW/cm2. (no averaging)
- Requires Programs to provide safe work to employees and contractors; includes inspection

## Related Standards

- OSHA 1910.147 - Lockout/Tagout of Power
- Requires lockout / tagout of power during maintenance to prevent excessive exposures
- OSHA 1910.132 - Personal Protective Equipment
- OSHA 1910.145, 1926.200 - Signs and Tags (Hazard Warning Signs)

## Consensus Standards:

-   The following organizations provide information and guidelines regarding RF use and protection.
- American Conference of Governmental Industrial Hygienists (ACGIH) provides Threshold Limit Values for RF/Microwave Radiation
- Institute of Electronics and Electrical Engineers (IEEE) /American National Standards Institute (ANSI) (U.S.)
- International Commission for Non-Ionizing Radiation Protection (ICNIRP)

## Controls:

## Controls

- Utilize low exposure equipment & site configuration
- Use good equipment
- Control hazard areas
- Limit exposures
- Access Restriction
- Maintenance of Controls

## Controls

- Lockout/Tagout
- Signal Blocking or Blanking
- Prevent access to hazardous locations (Signs & Fences)
- Standard Operating Procedures
- Protective clothing

## Slide 15

## GSFC WFF Safety Program

## RF Protection Program

- Radio Frequency Radiation Safety is addressed in GSFC 1860.3
- RF source equipment are required to meet applicable RF standards when new and during its lifetime.
- RF hazard identification and periodic surveillance is performed by a competent person.
- RF Hazard Areas are Identified and Controlled.
- Controls and SOPs to reduce RF exposures to levels in compliance with applicable guidelines are mandatory.

## RF Protection Program

- RF safety and health training is conducted to ensure employees understand the hazards and control methods used.
- Periodic reviews of the program are conducted to identify and resolve deficiencies.
- Workers are encouraged to notify the Safety & Health Office or their local representative whenever potential hazards are identified.

## RF Protection Program

- New RF/MW sources are evaluated by the WFF RF Safety Committee.
- Employees are required to be trained in RF Safety and document training using the  GSFC form 23-35RF

## Emergency

- In the event of an emergency contact 911 from a base phone or 824-1333 from a cell phone.
- For Close Calls or Hazard Reporting contact the Safety & Health Office @ 2559 or 2518.

## WFF Sources

**AREA****	****	****	****BLDG                  ****	****RF SOURCE**
**(Main Base)**
**Radar 18****	****	****	****A-41****	****	****	****1 Mw**
**ASR-7****	****	****	****N-159****	****	****	****425 Kw**
**11 Meter****	****	****	****N-162****	****	****	****200w**
**  ****9 Meter****	****	****	****N-162 ****	****	****200w**
**  ****6 Meter****	****	****	****N-162 ****	****	****200w**
**  ****LEO-T****	****	****	****N-162 ****	****	****200w**
**  ****TOTS****	****	****	****N-162 ****	****	****200w**
**Satan Command ****	****N-162 ****	****	****10Kw**
**SCAMP Command****	****N-162 ****	****	****10Kw     **

- Information courtesy of NENS

## WFF Sources

**	****Area****	****	****	****BLDG                  RF Source**
**(****Main Base)**
**MIR VHF****	****	****	****N-162****	****	****	****100w**
**VHF 2****	****	****	****N-162 ****	****	****100w**
**Water Tower VHF****	****F-165****	****	****	****100w**
**Fire Station VHF****	****	****B-129****	****	****	****100w**
**VHF****	****	****	****E-7****	****	****	****100w**
**Mobile Command****	****Trailers ****	****	****1Kw **
**    ****Destruct**

- Information courtesy of NENS

## WFF Sources

**	****Area****	****	****	****BLDG****	****	****RF Source**
**  ****(Island) **
**Radar 3****	****	****	****Y-55****	****	****1 Mw**
**Radar 5****	****	****	****U-70****	****	****2.5 Mw**
**Command Transmitter****	****U-55**
**UHF (4 xmttrs) ****	****	****	****	****1 Kw**
**UHF (2 xmttrs) ****	****	****	****	****4 Kw**
**UHF (2 xmttrs)****	****	****	****	****100w**
**HF (2 xmttrs) ****	****	****	****	****1 Kw**
**HF (3 xmttrs)****	****	****	****	****100w**
**UHF-VOICE (8 xmttrs) ****	****	****	****1-10w, 4-30w, **
**	****	****	****	****	****	****	****	****3-50w**

- Information courtesy of NENS

## What Next?

- After completing this awareness training the worker and supervisor need to complete GSFC form 23-35RF and forward it to the Safety Office – Bldg. E-106 room 209.  The form can be found at:
-  _[http://gdms.gsfc.nasa.gov/gdmsnew/srv/GDMSNEWDatabaseObject?document_id=682](http://gdms.gsfc.nasa.gov/gdmsnew/srv/GDMSNEWDatabaseObject?document_id=682)_