3.4.1 Types
The main options for storage systems in the Storage Room are:
- compactus
- open shelving units
- closed cabinets with drawers.
Each of these has advantages and disadvantages, however, they would all be considered appropriate in the context of Conservation ‘best practice’ for storage. A combination of all 3 types is likely to provide the best method of housing Ancestral Remains safely and efficiently.
A compactus is the most efficient use of space, and modern designs have good vibration dampening. This type of system can be used for all Ancestral Remains in standard boxes. The moving units of shelves in a compactus allow good access for cleaning and they can be locked to give an extra level of security. The disadvantages can be that a unit, once installed, is difficult to reconfigure to house deeper-or taller-than-standard boxes. Also, in a low access, dark Store they are likely to remain in the same position for long periods. This can result in poor air movement with the consequent risk of insects taking up residence or mould developing. A program of regular repositioning and inspections can effectively manage this risk.
Open shelving units with adjustable shelf height provide good access with no vibration and are suitable for all boxed remains. They are ideal for housing non-standard-sized boxes such as those required for articulated skeletons because units with deeper shelves can be relatively easily substituted for standard units. Fixed open shelving allows good air movement and, if the lowest shelves are at least 15 cm above the floor, provide good access for cleaning. The disadvantage is that they take up considerably more space than a compactus to provide the same amount of storage.
Closed cabinets fitted with drawers are the most suitable option for unboxed Ancestral Remains and any objects incorporating Ancestral Remains that need to be segregated, such as sorcery objects. Well-designed, soft-close drawers will minimise vibration. Closed cabinets enable remains to be held in a dust-free environment and are the best option for the remains of individuals who are represented by only a small number of post-cranial skeletal elements. Their disadvantage is in being less accessible than a compactus or open shelving and, like open shelving units, taking up more space.
A sub-category of closed cabinets are sealed cabinets that can hold an environment specially designed for the types of Ancestral Remains they are to house. For example, mummified remains which are unstable require a low RH to ensure degradation is not activated. This type of cabinet would need to be custom-made and incorporate a sealed storage chamber of the required size and a sealed drawer in the base with a grate connecting it to the storage chamber. It should also have a hygrometer on the outside of the cabinet to allow monitoring or the internal RH without opening the chamber. This is a variation on the design used for climate-controlled showcases (Thompson 1990, pp. 106–15).
Depending on the nature of the remains being stored (see Section 3.1), all of these types of storage system could be used in the Storage Room.
3.4.2 Materials
There are numerous publications on suitable materials for storage systems. One of the most comprehensive is by Jean Tétreault from the Canadian Conservation Institute (see Tétreault 2009) which provides detailed criteria for the selection of Conservation ‘best practice’ materials.
While there are ways in which wood can be treated to make it suitable for shelving, metal ‘is the most effective shelving to use from the point of view of strength and durability and also from the conservation point of view’ (Museums and Galleries of NSW n.d.). Compactus, open shelving units and cabinets should be made from powder-coated metal to prevent corrosion.
Sealed cabinets must be made from powder-coated metal with a platinum-cured silicone, neoprene, polyethylene gasket (Tétreault n.d., p. 9) to ensure that the cabinet remains unaffected by the environment it is intended to hold. Rubber should not be used. [8]
Storage requirements for fluid-preserved specimens will be treated separately (see Section 3.6.2 Conservation Treatment/Isolation Room).
3.4.3 Storage boxes
Most Ancestral Remains can be stored in one of 2 sizes of standard boxes. These boxes are pre-cut from archival board and assembled as required. They have a slot-in-groove method of construction and have no metal components. For this reason, dimensions for the boxes before assembly and after assembly will be given to ensure sufficient space in both the Storage Room and in the packing materials storage space in the Receipt Space.
Some individuals, depending on their stature and the number of their bones present, may require 2 or more boxes (see Section 3.1, Footnote 1). These boxes must be able to be stored together and linked by their database records.
- Cranial storage boxes
These are designed to hold skulls and crania. If desired they can be used to store the post-cranial remains of an individual if those remains are small or for commingled bones. In its flat state the base of the box measures 63 x 93 cm and the lid measures 32 x 54 cm. When folded to make a box with a lid the dimensions are 29(l) x 20(w) x 19(h) cm.
- Post-cranial storage boxes
These boxes are designed to hold post-cranial remains, and their length is set by the likely maximum length of unarticulated, adult, long bones, and their width by the maximum width of an adult pelvis. In its flat state the base of the box measures 102 x 110 cm and the lid measures 39 x 88 cm. When folded to make a box with a lid the dimensions are 64(l) x 28(w) x 21(h) cm.
- Custom-made boxes
While the vast majority of Ancestral Remains can be held in standard-sized boxes there are exceptions such as those which have been mummified or which are artificially articulated. Burial packages may also require a custom-made box. The dimensions of such boxes are dependent on the individual remains. Based on experience at the NMA, very few of these boxes are likely to be required and, although they could be made in-house, the amount of equipment, expertise and materials required to make them to the standard of the other storage boxes is not justified when they can be ordered in small quantities from the supplier of the standard boxes.
Footnotes
[8] The selection of gasket material should be revisited at the time the cabinets are being selected because advances in the performance of plastics is likely to continue into the future.