Introduction

A hot cell is a specialized, heavily shielded containment chamber designed for the safe handling of high-activity radioactive materials. It has thick walls typically made of lead, concrete, or steel to block gamma and neutron radiation, and operators use mechanical manipulators (robotic arms) to perform tasks inside the cell without physical contact. It has multi-layered, lead-impregnated glass windows that provide visibility while maintaining protection.

PULSTAR Hot Cell Facility

The establishment of this hot cell facility enhances the efficiency and safety for all irradiation and post irradiation examination (PIE) activities at the PULSTAR. The customized hot cell is located in the southwest corner of the PULSTAR reactor bay.  It has six (6) inches of lead shielding with nominal interior dimensions of 4.4 feet wide by 3.2 feet deep and 3.3 feet tall.  There is a large leaded glass viewing port with two remote manipulator arms at the operator station, a large access door, a horizontal pass through with transfer tray, a vertical pass-through port for transfer cask access, an internal translating hoist, a dose calibrator housing, a penetration for running instrumentation cabling, and electrical service connections.  

The cell is equipped with access port seals and supply and exhaust air connections containing HEPA filters to provide a confinement boundary for the control of potential airborne contamination.  The interior of the cell is fabricated from polished stainless steel providing an impermeable barrier to facilitate decontamination. The horizontal pass through has a separate ventilation supply providing positive pressure while transferring materials into and out of the potentially contaminated cell environment.  This pass through is large enough to allow experimental apparatus extracted from reactor beamports to be inserted into the cell for servicing.  The vertical pass-through port allows the large transfer cask to mate with the cell from underneath to offload radioactive materials transferred from the reactor pool.  The transfer cask provides six (6) inches of lead shielding and is sized to allow objects within the dimensional envelope of a PULSTAR fuel assembly to be loaded and transferred.  An air operated lift raises the top of the cask into the bottom of the cell, where the internal chain hoist may be utilized to remove the heavy cask lid and contents.  The hoist runs on a rail inside the cell allowing it to translate left and right and place the cask lid and contents where needed.  A large access door provides personnel access to the interior of the cell for staging experimental apparatus and performing maintenance.

The cell operator will utilize the two remote manipulator arms which have an excellent X-Y-Z range of motion and can access the majority of the cell interior.  The operator station also provides local controls for operation of the internal hoist, the transfer cask lift, the horizontal pass-through transfer tray, ventilation fans, internal lights, and four switchable electrical outlet banks.  Additional penetrations are provided for instrumentation cabling and service connections as may be required to support experimental work.  A shielded dose calibrator housing located in the back right bottom corner of the cell allows for the installation of a suitable radiation detector for the assay of radioactive solutions or objects while contained within the cell boundary.

This project was supported by DOE NEUP Infrastructure project “Establishing a Hot Cell Capability at the PULSTAR Reactor“.