Equipment placement and workflow

In a radiopharmaceutical production facility, placement is even more important than in a normal chemistry laboratory. The need to keep operations separate and prevent both radioactive and chemical contamination is essential.

A list of hints on equipment placement is given in Table 4.3.

4.3.2. Workflow

Careful thought should be given to the workflow as the radioisotope passes from the cyclotron target to the chemical synthesis, to the packaging area, and finally out for distribution. The facility should be arranged so that the transfer from the cyclotron to the hot laboratory minimizes the radiation exposure, and minimizes the chances of transfer failure. The transfer should be carried out in ways that there is an easy access to the transport vessel in case of failure. An idealized scheme is shown in Figs 4.4 and 4.5. In Fig. 4.4, the orange arrows represent the raw material flow into the facility and the purple arrows represent the final product flow out of the facility.

Laboratory space should be physically separate from personal desk space, meeting space and eating areas. Workers should not have to go through a laboratory space where hazardous materials are used in order to exit from non-laboratory areas. Consider making visible separation between non-laboratory and non-laboratory space, for instance with different flooring.

In the same facility (Fig. 4.5), the personnel flow is shown as blue arrows with a clear boundary between the limited access areas and the free access areas.

TABLE 4.3. LOCATION MATRIX FOR PLACEMENT AND ACCESS OF EQUIPMENT (ADAPTED FROM REF. [4.6])

Radioactivity and

contamination levels Laboratory location and access None Low High

   Separated from public areas by door.

  Access limited to authorized personnel.

  Laboratory doors have appropriate signs for level of

radioactivity.

   Size of door openings to allow passage of all anticipated

equipment.

  Doors have locks which are locked when room is not occupied.

 Doors have restricted entry access (e.g. key card).

 Office areas located in free access areas.

 Access to area is through an anteroom or lower level area.

  Exit from the area through a frisker or whole body counter.

   Utilities are located in close proximity.

 Laboratories located away from outside walls.

  Surface material designed to minimize movement of gases or

liquids outside the perimeter walls.

   Working surfaces to be non-absorptive.

   Surfaces are scratch, stain, moisture, chemical and heat resistant.

  Surfaces should be continuous (no seams).

  Drawers to be of one piece construction.

   Reagent shelving to be equipped with lips to contain spills.

  100% outside air supplied.

  Flow from areas of low contamination to high.

   Visual pressure differential monitoring devices at doorway to

room.

   Audible and visual alarms for air system failure.

  Supply air to be HEPA filtered.

  Supply air system interlocked with exhaust to prevent

overpressure.

  Exhaust air to be HEPA filtered.

Fire rated hallway doors should have magnetic hold-open features, such that the door will close in the event of an alarm. Doors to laboratories should not be fire-rated unless necessary. Entryways should have provisions for mounting emergency information posters and other warning signage immediately outside the laboratory (for example, on the door). Each door from a hallway into a laboratory space should have a view panel to prevent accidents from opening the door into a person on the other side and to allow individuals to see into the laboratory in case of an accident or injury. Even in the anteroom where there is a purposely straight path, a window can be installed in the wall to allow people in the hallway to see inside the synthesis area in case of accident or emergency.

  Supply and exhaust systems outside radioactive areas for ease

of maintenance.

  Mixed hazardous waste disposal system in place.

  All penetrations sealed with non-shrinking sealant at the

containment barrier.

  All conduits and wiring sealed with non-shrinking sealant at the

containment barrier.

  Windows do not open to the outside.

   Observation windows installed at the containment barrier.

   PPE hooks and supplies at containment barrier.

  Hand washing sinks provided with ‘no-hands’ operation.

   Emergency eye wash facilities provided at every sink.

   Emergency showers provided in accordance with regulations.

 Drains to containment or hold-up vessels.

  Compressed gas cylinders located outside laboratory space.

  Portable vacuum pumps available.

   Emergency lighting provided.

  Electronic data transfer to outside areas.

   Laboratory equipped with a communication system

between high activity areas and outside areas.

TABLE 4.3. LOCATION MATRIX FOR PLACEMENT AND ACCESS OF EQUIPMENT (ADAPTED FROM REF. [4.6]) (cont.)

Radioactivity and

contamination levels Laboratory location and access None Low High

Laboratory areas with autoclaves should have adequate room to allow access to the autoclave and clearance behind it for maintenance. There should also be adequate room for temporary storage of materials before and after processing. Autoclave drainage should be designed to prevent or minimize flooding and damage to the floor. When using radioactive material, there must be separate spaces for eating and drinking which are outside the laboratory space. Security of laboratory and materials is a concern and there should be safeguards in place for this. If possible, the laboratory should be designed to allow separation of radioactive material use from other laboratory activities.

The requirements for placement of the hot cells must meet the two important criteria of workflow and air flow. The hot cells: should be placed so that they are near the source of the radioactivity coming from the cyclotron vault; should be placed so that they are near the air exhaust from the room; and should be within easy access of the hot cells when they are not in use to facilitate cleaning and maintenance. The hot cells provide additional shielding;

thus, their placement against a vault wall offers a considerable advantage. In

Cyclotron Cyclotron

Free Access Areas Restricted Area

Quality

FIG. 4.4. Schematic diagram showing the unidirectional flow of materials through the facility. Raw materials are shown as orange arrows and the finished product is marked by purple arrows.

the above diagrams, there is access to the hot cells from the rear through the restricted area. This area should be interlocked with radioisotope transfer so that there is never anyone in that area when there are high levels of radioactivity present.