Seed 2_557-20-101 - 2024-06-19_SD Rpt_ GC85A_Physicist Rp.pdf

The Medical Physics Experts

W E S TW E S T P H Y S I C S

3 0 3 3 9S u i t e 2 5 0 A t l a n t a , G A3 8 2 5 P a c e s W a l k S E 866-275-WEST (9378) www.westphysics.com

June 18, 2024

Ivan Ambrose Carl Vinson VA Medical Center 1826 Veterans Boulevard Dublin, GA 31021

RE: Radiographic Suite Shielding Design Evaluation – Carl Vinson VA Medical Center 1826 Veterans Boulevard, Dublin GA 31021

Dear Ivan Ambrose, Please find enclosed the radiation shielding design evaluation for your Radiographic suite. The first page of the shielding plan summarizes the total minimum required shielding for each applicable room barrier.

Additional information supporting the shielding recommendations constitutes the remaining sheets. You should retain a copy of this shielding design evaluation at your facility in the event that a regulatory agency wishes to verify the room’s shielding. We expect that a regulatory audit of the installation will take place, and an inspector will likely request this document at that time.

Thank you for the opportunity to take care of your radiation protection needs. Should you have any questions or comments about this shielding design, we would be happy to speak with you at your convenience. Please feel free to contact us at (866) 275-9378 or at shielding@westphysics.com.

Thank you, Drake Brookins, M.S., DABR Senior Medical Physicist

David Fair, B.S.

Medical Physicist

Enclosure: Radiation Shielding Design Evaluation

Radiation Shielding Design Evaluation

Performed by

Site: Carl Vinson VA Medical Center

1826 Veterans Boulevard Dublin, GA 31021

Room: X-Ray # A171 # A176

Unit: Samsung GC85A

Shielding Design Results (A171):

Barrier Function of Space Behind Barrier

Controlled or Uncontrolled

Occupancy Factor (T)

Distance (ft, in) Total Minimum Shielding Required

A-B Central Tech Area Controlled 1.000 8' 7-7/8" 1/32" lead or equivalent

B-C Restroom / Equipment Storage Uncontrolled 0.200 5' 9-5/8" 1/32" lead or equivalent

C-D Corridor Uncontrolled 0.200 9' 3-3/8" 1/32" lead or equivalent

C-D (Door) Corridor Door Uncontrolled 0.125 11' 2" 1/32" lead or equivalent

D-E R/F Suite Controlled 1.000 18' 9-5/8" 3/4" drywall**

(Standard 2 × 5/8" drywall panel construction sufficient)

F-F’ Control Room Controlled 1.000 11' 3-3/8" 1/32" lead or equivalent

E-G R/F Suite Controlled 1.000 18' 7-7/8" 3/4" drywall**

(Standard 2 × 5/8" drywall panel construction sufficient)

G-H Control Alcove Controlled 1.000 18' 11" 3/4" drywall

(Standard 2 × 5/8" drywall panel construction sufficient)

Floor Slab N/A N/A N/A N/A

Ceiling Roof Uncontrolled 0.025 10' 0" 1/32" lead, 1/2" standard density concrete, 18-gauge steel, or equivalent*

*Required concrete ceiling may already be in place. Please double check concrete ceiling thickness.

**Area will be shielded from RF room, details are on the RF room shielding design.

Facility Diagram (A171):

Note: Cardinal directions are approximate only. Shielding should be installed carefully and with respect to the function of the surrounding areas to ensure proper barrier thicknesses.

Shielding Design Results (A176):

Barrier Function of Space Behind Barrier

Controlled or Uncontrolled

Occupancy Factor (T)

Distance (ft, in) Total Minimum Shielding Required

A-B Work Area Uncontrolled 1.000 8' 9-1/8" 1/16" lead or equivalent

B-C Exam Room / Restroom Uncontrolled 0.500 5' 8-1/2" 1/32" lead or equivalent

C-D Corridor Uncontrolled 0.200 11' 1/2" 1/32" lead or equivalent

D-E Corridor Uncontrolled 0.200 15' 8-5/8" 1-1/8" drywall

(Standard 2 × 5/8" drywall panel construction sufficient)

E-F Corridor Uncontrolled 0.200 7' 6-3/4" 1/32" lead or equivalent

E-F (Door) Corridor Door Uncontrolled 0.125 7' 8-5/8" 1/32" lead or equivalent

F-G Central Tech Area Controlled 1.000 13' 1/4" 1/32" lead or equivalent

G-H Central Tech Area Controlled 1.000 17' 10-7/8" 7/8" drywall

(Standard 2 × 5/8" drywall panel construction sufficient)

I-A Control Room Controlled 1.000 12' 10-5/8" 1/32" lead or equivalent

Floor Slab N/A N/A N/A N/A

Ceiling Roof Uncontrolled 0.025 10' 0" 1/32" lead, 1/2" standard density concrete, 18-gauge steel, or equivalent*

*Required concrete ceiling may already be in place. Please double check concrete ceiling thickness.

Facility Diagram (A176):

Note: Cardinal directions are approximate only. Shielding should be installed carefully and with respect to the function of the surrounding areas to ensure proper barrier thicknesses.

Other Recommendations and Requirements

• Dressing Rooms shall be vacated of all personnel whenever scans are performed.

• If the X-Ray room ceiling and the ceiling of adjacent rooms does not meet the minimum requirement specified in the “Shielding Design Results” table, then all vertical barriers shall extend to overlap the ceiling shielding. Otherwise, all vertical barrier shielding shall extend to a height of at least 7 feet.

• Doors, windows, frames, conduits, and wall openings must be of the specified shielding equivalencies or greater and should have no voids.

• Joints between lead sheets should be constructed so that their surfaces are in contact and with an overlap of at least 1 cm.

• Any penetrations in a given barrier should be designed to afford the same shielding equivalency as that specified for the barrier. For example, pipes, electrical outlets, or other barrier penetrations must be wrapped, covered, or backed up with appropriate shielding-equivalent material.

• A qualified contractor with experience in shielded construction should be utilized and a follow-up inspection performed to verify the adequacy of the installation after completion.

• This shielding design is for the equipment layout and occupancy of adjacent areas as indicated on the attached drawing. If any of these parameters are changed, the shielding design will require re-evaluation by a qualified physicist.

• The shielding requirements specified in this plan review were based on the stated conservative workload(s). If the patient volume increases significantly, the shielding will require re-evaluation by a qualified physicist.

Regulatory Recommendations and Requirements

• The registrant must ensure that each radiation machine is labeled in a conspicuous manner, which cautions individuals that radiation is produced when it is energized.

• Viewing system(s) shall be provided to permit continuous observation of the patient during irradiation and shall be located so that the operator can observe the patient from the control panel.

• The operator shall be allotted no less than 7.5 ft2 of unobstructed floor space in the booth, exclusive of any encumbrance by the X-Ray control panel such as overhangs, cables, etc.

• The X-Ray control shall be permanently mounted in a protected area so that the operator must remain in that protected area during the entire exposure. This control shall be at least 40 inches from any point subject to direct scatter, leakage or primary beam radiation. If a mobile barrier is used to create the protected area, the barrier must be permanently mounted to the wall and/or floor.

Additional Shielding Design Calculation Information Carl Vinson VA Medical Center

All calculations were performed in accordance with industry-standard guidance as detailed in NCRP Report No. 147, “Structural Shielding Design and Evaluation for Medical X-Ray Imaging Facilities.” Wherever possible, vendor and model-specific information for the x-ray units and/or radioactive sources in question were used. Where appropriate, calculations account for attenuation by primary beam pre-shielding using the equivalent thickness values listed in Table 4.6 of NCRP Report No. 147. Patient throughput estimates as well as workload kVp distributions were used in the following calculations, based on average values contained in NCRP Report No. 147. The recommended shielding amounts are specified in a highly conservative fashion, which will allow for a broad range of patient workloads, technique factors, etc.

without creating a radiation exposure issue. However, if any major changes occur (i.e., replacement of the x-ray unit, facility/x-ray room structural layout and/or changes in the usage of the x-ray room surrounding areas), the facility administration is advised to seek the services of a qualified medical physicist to determine whether shielding additions would be needed in those cases.

All shielding design goals, occupancy factors and workloads are as specified in NCRP Report No. 147 unless stated otherwise.

Equipment Specifications and Workload (W) (A171):

Equipment Type kVp (maximum)

Patients per Week mA-min per patient Workload (W)

Samsung GC85A 150 275 2.5 687.5 mA-min/week

Equipment Specifications and Workload (W) (A176):

Equipment Type kVp (maximum)

Patients per Week mA-min per patient Workload (W)

Samsung GC85A 150 275 2.5 687.5 mA-min/week

Shielding Design Goals (P):

Area Type Shielding Design Goal (P) (mGy/week)

Controlled 0.10 Uncontrolled 0.02

Methodology:

For this shielding design evaluation, the fitting parameter method for shielding calculation was employed, based on manufacturer data and information provided by the user. The room will be used primarily for general purpose exams directed towards a table-top and chest bucky image receptor. Therefore, barriers in this room are considered to be both primary and secondary barriers; scatter and leakage radiation values were incorporated. This shielding evaluation assumed a conservative number of exposures per week, based on facility estimates of its typical weekly workload. Equation A.3 of NCRP Report No. 147 was used to compute required barrier thicknesses. Fitting parameters for this equation for lead, concrete, glass, and gypsum wallboard thicknesses were found in Tables B.1 and C.1. Patient exam technique was based upon the typical workload distributions defined in Table 4.3 of NCRP Report No. 147 along with facility estimates.

All barrier thickness calculations were performed in Excel. These are available from West Physics and may be furnished upon request of the detailed calculations.

Summary:

The above referenced calculations and recommendations are made by West Physics based on data provided by the facility planners and unit manufacturer. As such, the recommendations made herein are subject to that information’s accuracy. This shielding design is hereby certified and executed:

Senior Medical Physicist

06/18/2024 Date