Shielding Design for Lab

Shielding Design Project

Turnkey Radiation Shielding for a Research Laboratory

RADXION was commissioned to design and deliver a turnkey radiation-shielding solution for a new research laboratory housing a 150 kV X-ray diffraction system and a Cs-137 irradiator. The work encompassed conceptual engineering, detailed shielding calculations, fabrication drawings, and on-site integration of bulk shielding, penetration chases, and access controls.

150 kV XRD SystemCs-137 Irradiator≤ 0.02 mSv/h OutsideReady for 300 kV Upgrade

Objectives

Dose-Rate Control

Ensure external dose rates in adjoining offices and public corridors remain ≤ 0.02 mSv/h under maximum operating conditions.

Ergonomic Access

Integrate service panels and labyrinth entrance to facilitate routine maintenance without compromising shielding integrity.

Regulatory Compliance

Meet IAEA SSR-6, local radiation protection regulations, and building-code requirements for structural loads.

Future-Proofing

Allow for accommodation of a potential upgrade to a 300 kV X-ray source with minimal modifications.

Scope of Work

Phase 1Shielding Assessment & Calculations

Compute required barrier thicknesses for 150 kV X-rays (broad-beam geometry) and 662 keV gammas using point-kernel methods.
Model scatter contributions to control-room interior using Monte Carlo verification.

Phase 2Architectural & Structural Integration

Develop CAD drawings for 0.4 m–0.6 m thick high-density concrete walls (ρ ≥ 3.2 g/cm³).
Specify reinforced steel lintels for door and window penetrations.

Phase 3Penetrations & Labyrinth Design

Design cable and duct chases with double-offset dog-leg geometry to prevent streaming.
Detail a double-door labyrinth entry, including interlocked doors and warning lights.

Phase 4Shielded Viewing Window & Equipment Ports

Specify 50 mm lead-equivalent polycarbonate window with laminated safety glass backing.
Design shielded feed-through ports for power, data, and utilities with removable lead collars.

Design Considerations

Beam Geometry

Account for primary, scatter, and leakage radiation paths.

Occupancy Factors

Evaluate adjacent spaces for “controlled” vs. “supervised” occupancy classifications.

Structural Loads

Verify that additional concrete density does not exceed slab loading limits.

Serviceability

Include removable access panels for source replacement and wall-chasing.

Materials & Construction

High-Density Concrete	Iron-oxide–enhanced mix achieving 3.2 g/cm³, cast in-place.
Lead Sheet Lining	10 mm Pb sheets behind wall finishes in high-flux zones.
Steel Framing	S355 structural steel for door frames and lintels.
Sealants & Gaskets	Radiation-resistant silicone for panel joints; labyrinth door seals rated to –40 °C to +120 °C.

Safety Features & Compliance

Interlocks

PLC-controlled door interlocks with fail-safe relays on source drives.

Warning Systems

Exterior warning lights, audible alarms, and beacon chain tied into building fire system.

Survey Ports

Embedded labyrinth-sealed survey tubes for easy quarterly dose checks.

Documentation

Comprehensive shielding report, “as-built” drawings, and regulatory submission package for FANR approval.

Deliverables

Shielding Calculation ReportIncluding Monte Carlo validation plots.
Fabrication & Installation DrawingsFor walls, doors, windows, and chases.
Material Specification SheetFor concrete mix, lead lining, and sealants.
Compliance PackageWith IAEA SSR-6 justification, local permit applications, and safety datasheets.
Post-Installation VerificationOn-site radiation surveys and “Certificate of Compliance” for operational handover.