Ionizing Radiation Safety


Users of equipment or devices producing ionizing radiation including X-rays, must comply with State and Federal regulatory requirements as well as the JSNN internal procedures. All procedures must be current and in compliance with 10A NCAC 15 rules. Current X-ray generating devices covered under this program at JSNN include a Gemini X-ray diffractometer and a Nikon XT H 225 ST 2x Computed Tomography (CT) Scanner.

General user compliance and safety responsibilities

PIs, supervisors, and all other users of the X-ray producing devices are required to:

  1. Review the “JSNN Ionizing Radiation Safety Manual” as part of their safety training before they are granted access and allowed to use the equipment.
  2. Understand and conduct operations in an acceptable manner to minimize hazards to himself/herself and others.
  3. Wear a dosimeter badge while working with the X-ray producing devices.
  4. Report any concerns and malfunctions to their supervisor.

PI responsibilities

  1. The principal investigator (PI) is responsible for ensuring that all personnel in his/her area/group are properly instructed and trained about the nature of the X-rays, ionizing radiation hazards, and the necessary radiation safety procedures in the laboratory.
  2. PIs must make sure that students or other personnel under their supervision follow all safety requirements for exposure prevention and assessment.

ROEHS responsibilities

The JSNN Research Operations and Environment Health and Safety (ROEHS) is responsible for:

  1. Assisting all users and PIs by providing consultation, training, and certain services in matters of ionizing radiation safety compliance.
  2. Establishing and reviewing policies and program elements in conjunction with the  Safety Committee X-ray safety working group.
  3. Implementing and maintaining the X-ray exposure to As Low As Reasonably Achievable (ALARA) levels.
  4. Developing and implementing Ionizing Radiation Safety protocols, including annual training, surveys, dosimeter badge reporting, equipment interlock checks, and maintaining required compliance-required documents.

Equipment manager’s responsibilities

  1. Maintaining and sharing an updated copy of the JSNN Ionizing Radiation Safety Manual in the lab.
  2. Ensuring safe operation of the equipment, including interlocks and password protection.
  3. Providing and documenting annual equipment training for all users.
  4. Developing written Standard Operating Procedures (SOPSs) including safety requirements and making it available to personnel before operating equipment.
  5. Reporting safety mechanism malfunctions and shortcomings to ROEHS.

Requirements for becoming an authorized user


To be considered an authorized user and/or gain and maintain access to the X-ray generating equipment, user must satisfy the following requirements:



Provided by

Applies to

JSNN Lab Safety/CHP Training



All users

JSNN Hazardous Waste Training



All users

JSNN X-ray Radiation Safety Training



All users

Equipment -specific training


Equipment Manager

All users

Completion of the “Radiation Worker Registration Form”



All users

Receiving and wearing a dosimeter badge

Used daily and renewed quarterly


All users

Using the equipment log sheet


Equipment Manager

All users

Note: Individuals who work with or around X-ray generating devices but are not authorized users of the device must complete the initial X-ray Safety Awareness Training. Upon completion of this training, users will be given an option to decide if wearing  a dosimeter badge is warranted.

The following chart illustrates the required steps for becoming an X-ray generating device authorized user.

Requirements and steps for Becoming an Authorized X-ray Generating Device User at JSNN

Exposure prevention and assessment

JSNN is committed to minimizing the X-ray exposure and maintaining the exposure to As Low As Reasonably Achievable (ALARA) levels. This is achieved through training, inspections, monitoring, safeguards, shielding, and other exposure prevention and control mechanisms. The ALARA action levels at JSNN are defined as 2% per quarterly-monitoring period or 10% annually of the latest applicable occupational exposure limits. Exposure above ALARA levels will be investigated by RSO.

NC DHHS rule .0104 (a), Annual occupational dose limits for adults and JSNN ALARA action levels


Dose limit

Quarterly ALARA Action Level (2%)

Annual ALARA Action Level (10%)

Total Effective Dose Equivalent (TEDE)

5,000 mrem*

100 mrem

500 mrem

Total Organ Dose Equivalent (TODE)

50,000 mrem

1,000 mrem

5,000 mrem

Eye Dose Equivalent (EDE)

15,000 mrem

300 mrem

1,500 mrem

Shallow Dose Equivalent (SDE)

50,000 mrem

1,000 mrem

5,000 mrem

*Roentgen equivalent man (rem) measures biological damage dependent upon type of radiation and is the regulatory unit used for dose history

Other compliance requirements

A.  Posting requirements

For hazard communication and NC DHHS compliance purposes, the following documents, signs, and labels must be posted inside each room where X-ray generating equipment is present:

  1. A copy of the JSNN Ionizing Radiation Safety Manual, containing program, dosimetry, training, inspection, and all other required records.
  2. NC DHHS, Division of Health Service Regulation Notice to Employees (see appendix 1).
  3. An X-ray caution sign at the room entrance along with emergency contact information.
  4. An X-ray caution sign on the cabinet/enclosure and X-ray tubes.

B. Dosimeter badges

All users of the X-ray generating devices must wear their assigned personal chest dosimeter badge upon entering the room. Badges must be placed on the badge board inside the room before leaving the room. Badges are collected quarterly and submitted to LANDAUER for exposure analysis and report. ROEHS-Radiation Safety Officer (RSO) will review, approve, and provide the analysis report to the equipment manager for documentation and sharing with users. Individuals who work in rooms where X-ray producing devices are located but do not use the X-ray equipment will have an option to be enrolled into the program and receive a dosimeter badge.

C. Annual interlock check and survey

JSNN RSO will perform and document annual interlock checks as well as the annual survey, using a calibrated Geiger counter. Survey measures the radiation levels around the X-ray enclosure. Any survey readout above the background will be investigated and addressed by the manufacturer or a qualified third-party. Survey results need to be documented.

D. Program Assessment

Using the NC DHHS Radiology Compliance Branch Analytical Radiation Protection Program Assessment Form, the JSNN RSO must complete and sign the annual program review. Corrective actions are documented on this form.

E. Declared Pregnancy

Women who declare pregnancy will be registered into the protection program and will also be assigned a monthly fetal badge. Declared pregnancy shall be kept confidential unless the pregnant woman decides otherwise. Declared pregnant women who work around the X-ray producing devices (but not with the equipment) will also be required to comply with these requirements.

F. Training

Users of the X-ray generating devices must complete the initial JSNN X-ray Safety Training. An annual refresher training is required. Those working in the areas where X-ray generating equipment are installed, but do not operate/use the equipment, must complete the initial “X-ray Awareness Safety Training”. No refresher is required for this group. Although JSNN partners receive the same training and are assigned dosimeter badges, it is the responsibility of the partner’s safety representative to request and maintain the historic training and dosimetry records.

Registration of the X-ray Generating Devices

ROEHS registers all new devices with NC DHHS, Radiology Compliance Branch, within 30-days of the initial use of each X-ray unit. The device must be registered using the equipment form. The JSNN, as the facility providing the service, is also registered using the business application form. Any changes in equipment location, ownership, RSO, or application must be reported to NC DHHS. All radiation-producing devices to be surplused, donated or transferred to another North Carolina facility or other business, should be inspected by ROEHS before leaving the building. Under some circumstances, a device may be tagged or disabled by ROEHS to prevent its use. No attempt to energize or otherwise use the device should be made without prior notification of and approval from Radiation Safety.