Architectural Conservation Laboratory HKU Faculty of Architecture - July 2018 6 2.1Regular Plaster Samples Three representative samples of the regular plaster were obtained to evaluate the interior plaster; two were taken from an opening in the south wall of the Entrance Hall where a timber beam had previously been connected to the wall (shown in Figure 6). Samples of both the inner and outer plaster layers were collected (EH-P-L1-02 and EH-P-L2-01). Additional samples were collected from the debris pile of plaster that had delaminated from the archway to Service 3 (S3-P-L2-01). The samples are shown in Figure 7, Figure 8 and Figure 9. Sample locations are marked on the plan in Figure . Figure 6.Brick and plaster layers exposed at the south wall of the Entrance Hall where a timber beam had been previously installed. Samples of L1 and L2 plaster layers were obtained from this location. Figure 7. Inner layer of plaster (L1) taken from Entrance Hall. Sample name: EH-P-L1-02.Figure 8. Outer layer of plaster (L2) taken from Entrance Hall. Sample name: EH-P-L2-01.