Attachment3_Exhibit Conservation Guidelines.pdf

National Park Service

Musuem Conservation Services @ Harpers Ferry Center

Exhibit Conservation Guidelines Second Edition – 2018

Incorporating Conservation Into Exhibit Planning, Design and Production

Attachment 3 HAVO Design Build Contract

Figures and Tables Contents at a Glance

1 Conservation and the Exhibit Process

2 Checklist for Conservation Involvement

3 Contribution of Team Members to Preservation

4 Conservation Criteria Form

5 Exhibit Area Preservation Features and Control

6 Exhibit Case Preservation Features and Control

Map

Narrative Guidelines Case Details & Illustrations Technical Notes

Exhibit Conservation Guidelines • National Park Service •

Fig. 1: Conservation and the Exhibit Process

Exhibit Conservation Guidelines l\Aap

Development Exbibit De£inition ldentifKation of goals, tlemes,uibnia&:resouxes

Exbibit Design Development of p ical:relationships, concept & Wchnical design documents

Products Comervation Crituia

Conservation Bu.dget Cb;ct Condition Rep: tls

Cb;ct Treatment Proposals

Macroclimatic Control Specs Microclimatic Control Specs Specialiad Mount DesigllS Comtruction Material 'Jests

Rotation Schedule for O>jects Treatment D:lrumentation

Maint2nance Manual

Speciali. .d Mounts & Supports Productionlmpection Reports Treatmentof Cbjects

Exbibit Installation Assembly &installation of the e)(lubit st:tuctu:res &displayobjects

Exbibit Fabrication Consbuction of e)(lubit sbuctu:res acco:rding ro plans &specifications

Production

Division of Conservation • National Park Service •

Fig. 2: Checklist for Conservation Involvement Map

2.

3.

EXHIBIT DEVELOPMENT EXHIBIT PRODUCTION

Planning Phase Design Phase Fabrication Phase Assembly & Installation

1. Exhibit Object Selection

,/pre-exhibit condition survey ,/treatment needs assessment ,/conservation criteria for objects ,/exhibit duration limits for objects and rotation schedule ,/use of reproductions ,/loan requirements ,/transport requirements ,/planning of safe holding areas ,/safe photographic procedures

1. General Exhibit Design

,/use of open display vs. cases ,/overall floor plan ,/object layout ,/selection of macro vs. micro-climate environmental control ,/use of protective barriers and stanchions ,/selection of safe construction materials ,/basic design of object mounts

1. Exhibit Case Inspection

,/use of stable materials within display chamber

,/testing of case seal ,/testing of case ventilation ,/assessment of case access ,/assessment of environ-mental controlling chamber ,/assessment of physical security ,/evaluation of prototypes

1. Case Installation

,/control of construction dust and debris

,/installation of furniture, graphic/text panels

,/final inspection of cases ,/performance testing of cases ,/provision of exhibit maintenance manual

2. Space Selection

,/environmental conditions assessment

,/environmental requirements for the room vs. microclimates

,/room lighting assessment ,/risk and security assessment

2. Aesthetic Coordination

,/selection of safe decorative material and surface finishes

,/object appearance (amount of treatment)

,/appearance and geometry of object mounts

2. Case Furniture & Panels

,/application of safe construc-tion materials

,/ability to support objects over time

,/ability to safely attach object mounts

2. Object Installation

,/provision of sufficient time to safely install

,/object handling guidance ,/controlled storage of objects ,/installation of mounts

3. Financial Planning

,/cost of conservation reviews ,/cost of upgrading environmental conditions ,/cost of using conservation-grade materials and cases ,/cost of conservation treatment ,/special exhibit mounting costs

3. Exhibit Case Design

,/use of ventilated or sealed cases

,/degree of case seal ,/design of microclimate environmental control ,/access to display, lighting and maintenance chambers

3. Object Mounting

,/object handling guidance ,/construction material stability ,/adequate physical support ,/safe fastening methods ,/mount removability for maintenance/emergencies

3. Climatic Adjustment

,/installation of micro-climate equipment

,/adjustment of equipment ,/installation of monitoring equipment ,/staff instruction in exhibit maintenance

4. Scheduling Key Activities

,/preparation of exhibit space and ,/object assessments ,/treatment of objects ,/construction of mock-ups and prototypes ,/testing of new materials ,/fabrication inspections ,/special object mounts/supports ,/careful installation and adjust-ment of exhibit environment

4. Lighting System

,/development of appropriate lighting plan

,/separation of task lighting ,/establishment of restricted illumination levels ,/ultraviolet filtration method ,/reduction of infrared radiation ,/light chamber heat dissipation ,/production of lighting mock-ups

4. Lighting Installation

,/testing of overall room lighting

,/evaluation of specific room fixtures and lamps

,/testing of exhibit case lighting

4. Lighting Adjustment

,/setting of exhibit lighting to restricted levels

,/evaluation of heat build-up

,/metered documentation of final object lighting

EAM

MEMBER

Preparator

Fig. 3: Contributions of Exhibit Team Members to Preservation

Exhibit Conservation Guidelines

Map

TEAM

MEMBER

GOAL 1.

OBJECTS ARE ENSURED

PRESERVATION

MEASURES IN THE

EXHIBIT’S PLANNING

AND DESIGN

GOAL 2.

OBJECTS ARE WELL

DOCUMENTED FOR

COLLECTIONS MANAGE-

MENT AND TO FACILITATE

EXHIBIT WORK

GOAL 3.

OBJECTS ARE HANDLED

AND TRANSPORTED

IN A SAFE MANNER

THROUGH-OUT THE

EXHIBIT PROCESS

GOAL 4. OBJECTS

ARE SAFELY

INSTALLED AND

ADEQUATELY

SUPPORTED WHILE

ON EXHIBIT

Conservator 0 advises on the selection of objects

0 reviews exhibit design and advocates changes necessary to meet conservation criteria

0 provides written condition reports for objects

0 establishes written conservation criteria

0 assists in documenting loan objects

0 provides handling guidelines for objects

0 may serve as courier for special objects

0 advises on method of transport

0 tests new materials 0 discusses safe mounting techniques with curator, designer and preparator

0 may construct special mounts and supports

Curator/ Planner

0 considers condition and preservation needs of object in selection

0 facilitates decisions regarding object replication or rotation

0 reviews conservation criteria and design

0 documents special requirements for handling and mounting

0 oversees the holding area for objects and/or the installation of objects

0 follows the handling guidelines

0 institutes methods that limit the need for handling objects

0 discusses the most appropriate presentation of the object

0 advises on treatment and mounting options

Designer 0 incorporates conservation criteria into initial design

0 works recommendations by conservator and other team members to modify initial design

0 provides floor plans and schedules which include object identification and location

0 carefully records object dimensions to ensure adequate space

0 follows the guidelines incorporating any concerns into the design

0 utilizes sketches, photographs, or scale models to limit the need for handling

0 includes presentation and mounting of objects in the design

0 provides final drawings for object locations and mounting requirements

Preparator 0 incorporates conservation criteria into mount design and execution

0 never removes an object identification without instruction

0 follows the handling guidelines

0 takes thorough notes, sketches, and patterns to limit the number of times objects must be handled

0 designs and fabricates the mounts according to special conservation and presentation requirements

0 observes handling guidelines

Registrar 0 relates any criteria set by lenders

0 advises on security requirements

0 maintains and documents a current list of exhibit objects

0 ensures an accession number is affixed to each object

0 tracks movement of objects, maintains a location files

0 depending on the institution may oversee the holding area for objects and/or installation of objects

0 oversees the transport of both lent and owned objects

Manager 0 encourages mediation to achieve a successful balance between conservation and other criteria

0 ensures sufficient conservation funds

0 facilitates cooperation to ensure that documentation is complete and current

0 ensures that key responsibility such as for handling guidelines, providing a holding area, and overseeing installation of objects is assigned to team members

0 ensures installation schedule is realistic

0 facilitates cooperation to meet schedule and ensure safe installation of objects

Fig. 4: Conservation Criteria Form

Map

GENERAL OBJECT REQUIREMENTS NO YES

1. Conservation Treatment Required?

comments:

2. Custom Exhibit Support/Mount Required?

comments:

3. Protective Exhibit Enclosure Recommended?

comments:

SPECIFIC OBJECT REQUIREMENTS Level 1 Level 2 Level 3 Level 4

1. Physical Forces: shock, vibration, abrasion, earthquake comments:

2. Theft and Vandalism: unauthorized access, violent acts comments:

3. Fire: exposure to excessive heat, smoke, deposits comments:

4. Water: flooding and building system failures comments:

5. Pests: vermin, rodents, birds and other animals comments:

6. Contaminants: indoor and outdoor gases, particulates comments:

7. Light Radiation: including UV, IR, and visible light comments:

8. Temperature: high/low/fluctuating comments:

9. Relative Humidity: high/low/fluctuating comments:

NOTE: Level 1= no protection; Level 2= Minimal; Level 3= Moderate; Level 4= Maximum

Fig. 5: Exhibit Area Preservation Features and Controls

Map

FEATURE LEVEL 1 LEVEL 2 LEVEL 3 LEVEL 4

1.

Physical security

No special security features

Minimal security Sample features: Infrequent staff presence; conventional door and window locks; low level alarms; voluntary rope and stanchion barriers to control visitors; no visitor entry control

Moderate security Sample features: Periodic presence of trained staff;

reinforced entry doors; high security locks; alarmed doors and window glazing; low-level electronic surveillance and alarm technology; limited visitor entry controls

High security Sample features: Level 3 plus full-time trained staff;

security guards when required; integrated security design by a security specialist; surveillance cameras tied to a central dispatch

2.

Fire safety and disaster protection

No special protection features

Minimal protection Sample features: Exhibit design facilitates object removal during emergencies;

plumbing locations are controlled; localized use of fire extinguishers

Moderate restrictions Sample features: Level 2 plus the use of high fire-rated construction materials; fire-resistant carpeting and drapes;

fire detection and suppression devices

High restrictions Sample features: Level 3 plus review of exhibit design by specialists; properly trained staff; electronic sensors/alarms tied to a central dispatch

3.

Biological pest protection

No special protection features

Minimal pest control Sample features: Unrestricted door and window opening policy; periodic pest inspections; conventional exhibit cleaning program

Moderate pest control Sample features: Inspection of all exhibit items prior to installation; routine, periodic inspections; use of trained staff and pest trapping devices;

enclosure of vulnerable objects

High pest control Sample features: Level 3 plus exhibit design review by pest specialist; no use of organic props; regulation of climate to control pests; insect resistant enclosures

4. Interior environmental control

No special control features

Minimal control Sample features: Seasonal reliance on building air-conditioning system; control over temperature, minimal control over relative humidity and pollutants

Moderate control Sample features: 24 hour a day reliance on building system;

moderate control of environment; well insulated exhibit space with vapor barriers included

Maximum control Sample features: Level 3 plus wide ranging climatic control; zoned building system for separate exhibit climate; diverse, ideal conditions are maintainable

5.

Exhibit lighting control

No special control features

Minimal control Sample features: Daylight and artificial lighting is minimally controlled; restrictions focus on visible light levels reaching objects

Moderate control Sample features: Moderately restrictive range of visible light, ultraviolet and infrared radiation; use of visitor activated lighting sensors

Maximum control Sample features: Level 3 plus highly restricted range of visible light, ultraviolet and infrared radiation; zero light on objects when exhibit closed

* An exhibit area can combine different levels of features and controls

Fig. 6: Exhibit Case Preservation Features and Controls

Map

FEATURE LEVEL 1 LEVEL 2 LEVEL 3 LEVEL 4

1.

Physical security

No special security features

Minimal security Sample features: Conven-tional construction materials; tamper-resistant screws and fasteners or locks

Moderate security Sample features: Construc-tion materials with higher resistance; concealed screws tamper-resistant fasteners;

locks and low-level alarms

High security Sample features:

Level 3 plus highest rated construction materials; high level locks, sensors, and alarms tied to central dispatch

2.

Construction material restrictions

No special construction restrictions

Minimal restrictions Sample features: Conven-tional museum case construction;

sealed wood products

Moderate restrictions Sample features: Use of high-quality materials and finishes;

low -VOC** emitters, sealed wood products

High restrictions Sample features: Use of inert materials, no wood products or potential VOC emitters

3.

Air seal (airtightness)

No special sealing features

Minimal to moderate seal Sample features: Conventional construction; standard design for removable panels, doors, and glazing; standard tolerances for joined materials

Moderate to tight seal Sample features: Strict tolerances for joints and seams; well-sealed gaskets on removable panels, doors, and glazing; use of caulk sealant; closely spaced fasteners

Hermetic seal Sample features: Level 3 plus airtight design and construc-tion; use of specialized sealant, gaskets and fasteners;

atmospheres are commonly filled with inert gas

4. Interior environmental control

No special control features

Minimal control Sample features: control based on passive case design, construction material selection, and case seal

Moderate controls Sample features: Level 2 plus the inclusion of passive environmental modifying agents (absorbers, scavengers)

Maximum control Sample features: Control based on active (micro) mechanical system; highly restricted environmental ranges

5.

Exhibit lighting control

No special control features

Minimal control Sample features: Separate lighting compartment with own entry; restrictions limited to visible light range

Moderate control Sample features: Level 2 plus moderate restrictions on ultraviolet and infrared radiation; visitor activated lighting

Maximum control Sample features: Level 3 plus highly restricted range of visible light, ultraviolet and infrared radiation; no heating of objects or case interior

* A single exhibit case can combine different levels of features and controls ** Volatile Organic Compounds

Charts and Tables Map

1 1:2 Checklist for the Exhibit Planner

2 1:4 Exhibit Object Condition and Recommendation Form

3 1:6 Exhibit Object Rotation or Substitution Report Form

4 1:12 Exhibit Maintenannce Tasks and Schedule

5 2:1 Temperature and Relative Humidity Monitoring Options

6 2:11 Exhibit Pest Incident Report Form

7 4:2 Exhibit Lighting Relamping Schedule Form

Narrative Guidelines Case Details & Illustrations Technical Notes

1:2 Checklist for the Exhibit Planner Map

Exhibit Conservation Schedule

TITLE: _ OPENING

DATE: _ EXHIBIT

LOCATION: _

OTHER VENUES: _

SCHEDULE ADMINISTERED BY: _

CLOSING DATE: _ _

SCHEDULING REQUIREMENTS

TASK DATE ASSIGNED RESPONSIBILITY DATE COMPLETED NOTES

EXHIBITION DEVELOPMENT

objects chosen objects conditioned conservation criteria developed objects catalogued and numbered housed in a safe location special display requirements discussed with designer preliminary design reviewed final design approved

PRODUCTION AND INSTALLATION

case prototype plans developed material selection completed case prototypes built case prototypes tested case prototypes approved special mounting discussed custom object mounts prepared treatment of objects completed environmental systems tested exhibition construction completed gallery cleaned objects installed

MAINTENANCE AND DE-INSTALLATION

objects monitored for condition environmental conditions monitored:

temperature and relative humidity environmental conditions monitored:

pollutants environmental systems maintained:

temperature and relative humidity pollution control systems maintained objects removed at close of exhibition objects returned to storage exhibition dismantled

1:4 Exhibit Object Condition and Recommendation Map

Exhibit Conservation Guidelines

ACCESSION or LOAN NO.: REQUIRES TREATMENT: Y N CONSERVATION NO.:

OBJECT: MATERIAL:

EXHIBIT TITLE:

LENGTH OF EXHIBIT:

EXAMINED BY: DATE:

CONDITION BEFORE EXHIBIT

GOOD FAIR POOR STRUCTURALLY UNSTABLE DISFIGURED OTHER:

RECOMMENDATIONS

TEMPERATURE (°F): RELATIVE HUMIDITY (%):

LIGHT LEVELS (fc): OTHER:

MOUNTING REQUIREMENTS:

CHANGE IN CONDITION (complete when noticed or at end of exhibit)

NO VISIBLE CHANGE: Y N VISIBLE CHANGE: Y N DATE: INITIAL:

1:6 Exhibit Object Rotation or Substitution Report Map

Exhibit Conservation Guidelines

ACCESSION or LOAN NO.: LENGTH OF ROTATION: in months 3 9 18 6 12 24

SUBSTITUTE WITH OBJECT NO.:

OBJECT: MATERIAL:

EXHIBIT TITLE:

LENGTH OF EXHIBIT:

CONDITION BEFORE EXHIBIT

EXAMINED BY: DATE:

_GOOD _FAIR _POOR _STRUCTURALLY UNSTABLE _DISFIGURED _OTHER:

ROTATION OR SUBSTITUTION SCHEDULE

DATE PLACED ON EXHIBIT DATE REMOVED FROM EXHIBIT SUBSTITUTED WITH STAFF NAME

CHANGE IN CONDITION (to be completed when removed from exhibit)

NO VISIBLE CHANGE:_Y _N VISIBLE CHANGE:_Y _N DATE: PERSON:

1:12 Exhibit Maintenannce Tasks and Schedule

Exhibit Conservation Guidelines

Map

Exhibit Title:

Exhibit Location: Dates:

REQUIRED TASKS FREQUENCY DATES COMPLETED NOTES

A. DISPLAY SPACE

Inspection for physical defects Security review Object assessment Pest inspection Vacuum Dust Monitor temperature and relative humidity Review light levels Change filter in HVAC Annual HVAC maintenance

B. OBJECTS ON OPEN

DISPLAY

Object assessment Clean objects Security assessment

C. CASE EXTERIORS

Inspection of exhibitry Clean cases

D. CASE INTERIORS

Inspection of case interior Cleaning case interior Inspection of mounts Change monitoring chart download data logger Recondition/renew silica gel Examine pollutant monitor Replace pollutant absorber

E. OBJECTS

Check location Rotation Substitution Cleaning Treatment

2:1 Temperature and Relative Humidity Monitoring Options Map

Exhibit Conservation Guidelines

TYPE OF SYSTEM DESCRIPTION USE/COMMENTS1 APPROXIMATE

COST

MANUFACTURER

/ SUPPLIER

remote sensor chart recorders probe with cable connected to a chart recorder

Accuracy ±1°F and

±3% RH;

1-6’ cable;

some have alarms for high or low levels;

can have multiple recording channels.

$640-$2000 Omega Engineering, Inc. or various other firms hand-held electronic hygrometers and thermometers probe or sensor connected to a hand-held unit with digital display accuracy ±2°F and

±3%RH;

operates on batteries;

portable; some can be connected to remote recorders.

$250 and up Cole-Parmer psychrometer readings from a wet and dry thermometer are referenced on a chart to give humidity accuracy dependent on operator;

use distilled water;

wick must be clean.

$150 and up Cole-Parmer indicator cards a combination of cobalt and other inorganic salts that change color in response to relative humidity accuracy ±10%;

cheap;

useful as a visual indicator of a problem when dataloggers are used.

$1 per card Humidial Corp.

data loggers sensor with a memory chip that records data for future downloading accuracy ±4%RH;

can be left in place for up to one year;

no visual reading from the unit itself so problems may go undetected until downloading.

price from around $1,000

SmartReader 2 TRAK-R Logger or equivalent Hanwell Wireless recording hygrothermographs sensors are connected to pens that simultaneously record data on a chart connected to a revolving drum or disk accuracy ±2°F and

±2%RH;

allows on the spot reading of data;

some units record up to three months;

are already available in many institutions.

$250 and up Cole-Parmer Dickson hygrometers and thermometers small unit that displays either temperature, humidity, or both on a dial or digital display accuracy ±2°F and

±3%RH;

calibration must be checked frequently;

small enough to be easily hidden.

$50 and up Cole-Parmer

1 Accuracy may vary between units. The best published accuracy is given in this chart.

2:11 Exhibit Pest Incident Report Form

Exhibit Conservation Guidelines

Map

Exhibit Pest Incident Report Form

Examiner: _ Date: _

Exhibit title: _ Exhibit location:

Object(s) location:

Open display: _

Location of Pest Evidence and Museum Objects Affected

Closed exhibit case: _

Specific object(s) affected:

Specific materials damaged:

Identification of pests: _ Source of Identification: _

Pest Observation

Total Number of Pests Observed: living: _ dead:

Insect or Rodent Evidence:

Frass Cast larval skins Egg casing Webbing Specks Droppings Nesting materials Carcasses Staining Holes/tunnels Surface grazing Other

Isolation (list method): _ Pest Management Action To Be Taken

Mechanical cleaning (performed by):

Freezing (list duration/temp): _ Fumigation (list fumigant): _ Frequency of follow-up inspection: _ Implement area-wide monitoring:

Additional Comments: Reverse

4:2 Exhibit Lighting Relamping Schedule Form

Exhibit Conservation Guidelines

Map

The Maintenance Manual should include a schedule for relamping the exhibit lighting systems and for replacing any specialized filters.

Documentation of the lighting systems, lamp types and any filters or other special lighting features is critical to the maintenance of conservation approved lighting for the exhibit. The angle and spread of the beam are two very important variables that are often implemented incorrectly during relamping. This effects not only the aesthetics of the exhibit but light levels falling on the display objects.

The following form is an example that can be adapted to suit the particular lighting system used in an exhibit.

EXHIBITION LIGHTING SCHEDULE FORM

Exhibition:

Location:

Dates of Inspections:

LAMP

TYPE

MANUFACTURER PART NO. WATTS VOLTS LAMP QUANTITY OBJECT OR

LOCATION

LIGHT

LEVEL

BEAM

ANGLE

Case Details and Illustrations

1 Exhibit Case Styles

2 Case Lighting

3 Access and Security

4 Construction Materials

5 Environmental Control

6 Case Air Seal

Map

Narrative Guidelines Technical Notes

Exhibit Conservation Guidelines • National Park Service • April 1999 Content Development and Illustrations by Toby Raphael and Kevin Brookes

Contents in Detail

Exhibit Case Styles l:A Free-Standing Case Examples l:B Free-Standing Case Examples l:C Wall Case Examples l:D Wall Case Examples l:E Exhibit Case Anatomy l:A Free-Standing Case Examples, #l Map l

Within the tremendous range of case styles, two primary categories exist: free-standing and wall cases.

The examples shown here represent the basic range in free-standing cases and typify how these designs affect the viewing of exhibit objects, case access exhibit lighting and environmental control.

Of utmost importance is the enclosure's ability to provide a protective micro-environment, control the ingress of pests and airborne pollutants, and reduce environmental instability. With regard to these factors each free-standing case design performs differently. The design variables that impact preservation performance are: the degree to which the case can be sealed; whether an environmental maintenance chamber and lighting chamber can be included; the type of glazing and the number of glazed panels or walls used; whether epoxy/welded joint vitrines or frames for structural glazing are used.

Aquarium Case with Integral Lighting

Backwall Case

Table Top Case

Pedestal Case

Framed Backwall Case

Framed Case

Exhibit Conservation Guidelines • National Park Service • April l999 Content Development and llustrations by Toby Raphael and Kevin Brookes l:B Free-Standing Case Examples, #2 Map

• Vitrine tops with epoxy\welded seams are light weight and are easily sealed; however, they provide limited physical security. Tall vitrines can endanger objects when lifted-off to access display material.

• Wood or metal structural frames can be engineered to impart strength and physical security; however, they dramatically increase the potential of air infiltra-tion; gasketing and caulk sealants will be needed.

• The design and location of access doors are critical because of size and weight limitations, and sealing difficulties.

• Multiple, inline glazed panels increase not only case volume but the amount of linear seals required;

joining hardware and caulk sealants will be needed. Moveable panels present special engineering challenges and may require special hardware.

• Introduction of solid, stationary walls facilitates access door design, physical stability and case rigidity; vapor permeability of walls for micro-environments and dimensional stability of wall-to-glazing joints must be considered.

• In integral lighting systems fixtures and lamps attach directly to the case. Lighting attics must be sealed, separate chambers with adequate ventilation to ensure no heating of exhibit objects. The principal lighting challenges are to control radiation levels and heating at such close proximity to objects.

Multiple-Panel

Double-Sided Case

Single-Sided Case

Framed Backwall Case l:C Map Wall Case Examples, #l 3

The examples shown here represent the basic range in wall cases; they share the feature that they attach and protrude from a vertical wall or are embedded within a wall cavity. These examples typify how designs affect the viewing of exhibit objects, case access, exhibit lighting and environmental control.

Of utmost importance is the enclosure's ability to provide a protective micro-environment, control the ingress of airborne pollutants and pests, and reduce environmental instability. With regards to these factors each wall case design performs differently.

The variables that impact preservation performance are: the degree to which the case can be sealed;

whether an environmental maintenance chamber and lighting chamber are included; the type of glazing used and the number of glazed panels and solid walls; and whether epoxy-welded vitrines or frames for structural glazing are employed.

4-Sided Vitrine Case

5-Sided Vitrine Case

Shadow Box Case

Angled Rail Case l:D Wall Case Examples, #2 Map

• Wood or metal structural frames can be engineered to impart strength and physical security however, they dramatically increase the potential of case leakage; gasketing and caulk sealants will be needed.

• Multiple, inline glazing panels increase not only case volume but the amount of linear seals required, extruded joining hardware and caulk sealants must be employed. Moveable panels present special engineering challenges and require special hardware.

• Interior walls can facilitate access door design.

As these surfaces (including ceilings and floors) can be pre-existing, vapor permeability and temperature transfer can be problematic.

Dimensional stability of wall-to-glazing joints must be considered.

• In integral lighting systems fixtures and lamps attach directly to the case. Lighting attics must be sealed; separate chambers with adequate ventilation to ensure no heating of exhibit objects.

The principal lighting challenges are to control radiation levels and heating at such close proximity to the objects.

Full Height Multiple Panel Case

Hinged-Door Multiple Panel Case

Framed Multiple Panel Case l:E Exhibit Case Anatomy

S

Exhibit cases are enclosures comprised of an exterior structure with one or more viewing windows and interior compartments. All cases have an object display chamber; not all cases have an environmental maintenance chamber and a lighting chamber or attic. Lighting attics are only required when exhibit lighting originates at the case.

The environmental chamber is used for humidity and chemical pollutant controlling equipment.

These materials can also be located within the display chamber in exhibit furniture or behind objects.

Preservation concerns generally focus on the design and materials used in the construction of the interior compartments.

The primary conservation concerns are: the use of non-hazardous construction materials; air circula-tion between the maintenance and display chambers and maintaining their level of seal from the room;

adequate venting of the lighting attic and its sealed isolation from the other chambers.

Wall Case

Light Attic

Display Chamber

Environmental Control Chamber

Display Chamber

Display Chamber

Case Lighting

2:A Lighting Source Locations

2:B Lighting Duration and Intensity Controls

2:C Integral Lighting Access

2:D Lighting Compartment Heating

2:E Light Modifying Devices

2:F Incandescent Lighting

2:G Fluorescent Lighting

2:H Fiber Optic Illuminator Locations

2:I Fiber Optic Lighting Options

2:A Lighting Source Locations

There are two methods of lighting exhibit cases:

external lighting from the room's ceiling (or walls) and lighting that is integral to the case. Ceiling lighting is preferred from a preservation perspective because electrical fixtures and heat generating lamps are kept at a distance from the display objects.

Ceiling lighting, including recessed and surface mounted lights, is generally installed as angled lighting, and as down lighting. The primary disadvantage of angled lighting is glare, reflection and shadows from visitors. The 30 degree angle shown below is suggested for optimal lighting.

Down lighting avoids glare but shadows from objects can be problematic. Case ceilings can be fabricated to include protective diffuser panels or films. Advantages of integral lighting include:

• light source concealment;

• object by object adjustment of illumination levels;

• flexibility to customize lighting for changing content.

Ceiling Angled Lighting Ceiling Down Lighting Integral Case Lighting

2:B Lighting Duration and Intensity Controls

To minimize exposure of light sensitive objects to case lighting, reduce the duration and intensity of exposure. There are 5 major control methods avail-able: manual switching, manual dimming, pre-set switching, pre-set dimming and use of motion sensors.

• Manual switching- involves manual activation of lights by visitors or staff: on-off switching of either entire circuits or individual fixtures.

Inexpensive remote switches can be added to cases and operated by staff from a central desk.

• Manual dimming- involves the adjustment of light levels for a single case or for an entire exhibit area.

Consider installing fixtures with individual dimmers so that individual lamps can be turned down- dimmer levels should be fixed and made tamper-proof.

• Pre-set dimming- involves more sophisticated, programmable dimmers. Specific lighting levels are consistently obtained and gradual ramping of light levels is possible. Systems are usually employed with occupancy or automatic sensors.

• Pre-set programming- electronic control panels can be set for multiple functions of timing and programmable dimming circuits.

• Occupancy (motion) sensors- involve sensors that determine exhibit visitor movement and switch lighting on-off accordingly. They are linked to manual or pre-set dimmers and usually rely on ultrasonic or passive infrared technology.

Manual switching, remotely controlled by staff. Duration of an object's exposure to light is dependent on the attentiveness of museum staff.

Manual switching controlled by visitor. Manual switches are easy to install, however, adding a timer is a safeguard against the lighting being left on.

Pre-set dimmer with visitor occupancy sensor control. These systems are the most reliable but must be matched with the lighting equipment;

some are incompatible.

2:C Integral Lighting Access

Lighting compartments must be isolated from object display chambers: no air exchange between the chambers should occur. Lighting fixture adjust-ment and lamp maintenance should be accomplished through an independent access door which has its own security features.

The same key should not permit access to the dis-play chamber and objects. Doors should be designed to provide sufficient space to install and manipulate fixtures and lamps-large enough for a technician to reach all fixtures. Special attention should be given to the support for larger or heavy doors in order that they be held safely open during maintenance procedures. Hinged doors should open "up" rather than "down". All lighting compartments require ventilation; those located under or to the side of the display chamber require insulation to reduce heat transfer.

A lighting compartment in the base of the case can incorporate a fiber optic light illuminator, or below deck lighting fixture.

Wall case lighting may be accessed either from the front or from the rear if a maintenance corridor is available.

Lighting fixtures attached to hinged doors are easy to maintain, however, may be difficult to aim.

Placement of fixtures in large free-standing cases, should not locate lamps out of reach.

2:D Lighting Compartment Heating

A significant disadvantage of integral case lighting (besides the risk of electrical fire) is over-heating of the display chamber by poorly designed lighting compartments. Adequate ventilation and insulation of lighting compartments are critical to prevent heat transfer. Fan cooling designs should also include convection cooling for periods of mechani-cal failure. To ensure adequate heat dissipation consult a mechanical engineer to determine the BTU's produced, the size of the vent area and air flow requirements. Key factors include lamp wattage, compartment size and room temperature.

Fans should be oriented to evacuate hot air from the compartment.

Insulated glass panel is an option.

Lamps and fixtures that do not generate excessive heat can be cooled through natural convection, using well-designed and filtered, ventilation openings.

Locate fans near and above the lamps. Utilize equal opening sizes for the air entering and exiting. Incoming air must be filtered.

Insulate below deck lighting compartments.

Heat transfers to objects in 3 ways :

• Radiation Heating - electromagnetic wave motion (heating of objects without warming the air between them and the lamp);

• Conduction Heating -transmission from molecule to adjoining molecule (heating of display chamber material through the adjoining case structure);

• Convection Heating-Transmission by air motion: warmer surfaces to cooler (heating of display chamber air through contact with the heated glazing surfaces).

Hot air from lamps located in the base of a case must be mechanically vented from the base area, or the case side.

2:E Light Modifying Devices

Light modifying devices can easily be introduced into light compartments between the light source and the objects. Applications include layering materials and directional screens. The selection of light modifying devices should be matched to the lighting system being used. Lighting compartment dimensions must be large enough to accommodate the devices, and to prevent over heating of flammable materials.

Damaging radiation can be efficiently minimized by filters which control both the intensity of light reaching the objects and its UV and IR components.

Glass or synthetic (plastic) filter systems can be used to eliminate UV radiation below 400 nm: Either soft, thin plastic film, or rigid plastic sheet is available.

Lighting diffusers, louvers and baffles can be used to direct or diffuse light; reduce hot spots and glare;

and hide fixtures, insects, and debris.

Thin sheet materials are available as:

flexible diffuser, UV filters, IR filters, and tinted light reduction films.

Rigid sheet materials are available in glass, acrylic and polycarbonate;

UV filters, diffusers and lenses.

Rigid louver panels are available in plastic and metal as amplification or parabolic grids, light direction grids and glare reduction panels.

Louvers can be placed below the transparent panel to hide debris that can accumulate over time. Light modifying materials employed within the display chamber must be conservation appropriate materials.

Micro louvers panels are used for light direction and glare reduction.

2:F Incandescent Case Lighting

Currently, low voltage (quartz halogen) incandes-cent lighting is the most common light source for exhibit cases. Both traditional incandescent and quartz halogen lamps produce a desirable 2800° to 3000°K color temperature and have good color rendering.

A great range of fixtures, lamps and beam varieties are available, however, they have several disadvantages:

• lamps are often too bright at the close distances;

• lamps produce more heat than light.

Design incandescent lighting systems to avoid excessive visible light levels and overheating:

• whenever possible, use low voltage systems with low wattage lamps (ie. 20-35 watts);

• use the correct beam width for the application;

• adequately vent the lighting compartment;

• keep at least 4 feet between lamps and objects;

• set lamps as far from transparent plastic panels as possible within the lighting compartment;

• use adjustable fixtures that accept filters.

Barn doors or baffles

Cube cell louver

UV & IR filters

Lens spreaders & focusing aids

Adequately ventilate incandescent lamps: locate vents above lamps and distance lamps from flammable materials such as acrylic panels.

Consult manufacturer’s product data.

Snoot shield

Accessories that are available for incandescent fixtures.

Locate aim-able fixtures towards the front of the lighting chamber.

Fluorescent lighting can also be integrated for diffuse lighting.

For lighting flexibility within compartments install fixtures on moveable track.

Low voltage transformers are heat producers: fixtures can have individual transformers, or share a single remote transformer.

Track fixtures can have individual dimmers: pro-cure fixtures with the ability to hold lighting control filters and lenses.

Quartz halogen lamps should incorporate an infrared reflective coating and be used in combination with UV absorbing filters.

PAR lamps are parabolic aluminized reflectors that are available in low wattage halogen or standard versions.

2:G Fluorescent Lighting

Fluorescent tubes are frequently used for ambient case lighting. The light is diffuse and non-directional and therefore not suitable when individual objects or text need to be illuminated at different levels. New, better quality fluorescent tubes offer better color rendering, and with the installation of dimming ballasts, light levels can be dimmed to within ten percent of full value without affecting light quality.

Placement is usually at the top of an exhibit case, causing over-lighting at the top and insufficient lighting at the bottom. Lighting in cases containing sensitive artifacts are of particular concern as foot candle levels much be adjusted according to object sensitivity, sometimes resulting in areas in the case with insufficient illumination.

Other associated problems are:

• designs frequently call for too many fixtures, and lower illumination levels cannot be obtained;

• heat from the fluorescent fixtures and ballasts heat objects in the display chamber, and destabilize the interior climate unless well vented;

• most tube lamps emit unacceptable levels of UV. If conventional or compact lamps are used the lighting compartment should be carefully designed and tested. Design options include:

• selecting lower UV lamps and introducing UV filters;

• venting the compartment adequately and locating the ballast outside of the compartment to reduce heat

• using block out masks, louvers and baffles to control light.

Point Source Lighting A compact fluorescent lamp can be successfully utilized as a point source of lighting with the use of mirrors or reflective baffles, as indicated above.

Compact Fluorescent Lamps are available in a wide range of shapes and styles and can be successfully integrated into lighting compartments. They are useful at short distances;

the tube emits little heat; housings and lenses can be purchased which filter UV; low wattage lamps (ie.7-9 watts) are generally sufficient for most applications. Some lamps can be dimmed with the use of electronic dimmers and dimmable ballasts. Conventional fluorescent lamps in free-standing and wall case applications.

2:H Fiber Optic Illuminator Locations 8

Fiber optic illuminators use a focused light source to direct light to a nosepiece containing multiple fiber optic cables. The light source can be MR-16 tungsten halogen, metal halide, or solid state LED. Depending on the light source, the illuminator will be either fan or convection cooled. The location of this equipment necessitates careful planning because illuminators require:

• electrical power (usually 110 volts);

• efficient cooling/ventilation systems;

• proximity to the lens (less than 30 feet);

• a clear path for optical cables to the lenses;

• physical access for maintenance.

When enclosed within the lighting compartment caution needs to be exercised to avoid heating of the display chamber. Adequate air flow is required to dissipate heat that is generated. Insulation will be required for illuminator locations under the dis-play deck.

Remote Location Illuminator located remotely to the case, either behind a wall or in the ceiling above

Below Deck Location Illuminator located in the base of a case

Lighting from Below When display objects require lighting from below fiber optic systems can be used effectively if the heating and excessive illumination issues are addressed. Because of the problem of heat dissipation, conventional incandescent fixtures, lamps and low voltage transformers are problematic for this applica-tion. Caution must be exercised in the case design phase to prevent overheating:

• include insulation between the illuminator and the display chamber;

• provide adequate ventilation.

Attic Location Illuminator located in the attic of a case

The benefit of using a fiber optic system is not only the control of UV and IR, but the light source can be located remotely and the light distribution locations can be hidden. A wide range of lenses (luminaires) can also be used. Lenses vary in quality, beam spread and beam distance. Eyeball (swivel) luminaires offer more flexibility than fixed down lights; mirrored lenses augment the angle of illumination.

Fibers, made of either glass or acrylic, can be fed into exhibit structures to allow lighting from the ceiling, walls, case corners or floor.

Light can be focused onto objects with accuracy;

from a fine pin point to a wash of light, offering a high degree of illumination control.

Illumination levels can be controlled by:

• choice of lens;

• the use of neutral density lens filters;

• size and length of cable;

• lamp wattage;

• light reducing screens at the lamp.

To provide optimal coverage of the case interior mount the lens in a beveled ceiling.

Care should be taken when bending acrylic cable in tight curves as stress can cause fractures and eventual breakage.

Corner track is available for installing lenses behind case mullions, or along the edges of the case frame.

One illuminator can furnish dozens of independent light sources. The case above utilizes ceiling lenses (or luminaires) and corner track. Any entry of fixtures or cable into the exhibit area must be properly sealed to ensure environmental stability.

Access and Security

3:A Lift-off Case Access

3:B Hinged Door Access to Cases

3:C Specialized Case Access

3:D Physical Security

3:E Structural Security

3:F Electronic Security

3:A Map Lift-off Case Access 1

Both curatorial and conservation input should be considered in the design of case access. Lift-off vitrine size and weight should allow access by a single individual whenever possible.

Consider the following when establishing case access design:

•frequency of use •time required to access •number of staff required •difficulty of re-securing component •difficulty of creating seal

Lift-off vitrines should never be so large that they cannot be lifted safely over the objects inside the case.

30"x30"x30" is generally considered the largest vitrine safe for lift off access. Large units weighing over 75 lbs. are to heavy even for two people to move safely.

Glass components are just over twice as heavy as equally designed items in acrylic or poly carbonate. Large glass vitrines or glazed panels should be of laminated safety glass to prevent acci-dental damage to display objects.

3:B Map Hinged Access Doors to Cases 2

Both curatorial and conservation input should be considered for the design of case access. Door size and weight should allow access by a single individ-ual whenever possible. Glass doors are just over twice as heavy as equally designed doors in acrylic or poly car-bonate.

When establishing case access design; consider the following:

•frequency of use •time required to access •effect on case stability •hardware selection and lock location •difficulty of re-securing door •difficulty of creating case seal

Hinged doors that are oversized may need additional support such as pneumatic cylinders or supporting legs to prevent destabilizing the case.

Special attention is required to properly seal the hinge area in well-sealed cases. Hinged doors tend to pinch the gasketry nearest the hinge.

3:C Map Specialized Case Access 3

Large glass panel doors have traditionally presented a challenge to exhibit designers. Generally the glazing is set in a track and slid to one side to enter the case. Where the glazing is overlapped a gap remains.

From a preservation perspective this design is unsatisfactory because of the large gap size (even when plastic extrusions are utilized) and the difficulty of sealing the case. Without careful attention to detail, this case design can result in dusty and insect-filled enclosures.

New, specialized hardware is available that allows even heavy, over-sized glass panels to pull forward and roll to the side on hanging track.

These sophisticated hinges allow for a relatively tight seal and single person access. In some cases a removable mullion is used to ensure the glass seats correctly against a gasket.

Large multi-panel wall case with rolling door hardware

Large free-standing case with single mobile door

3:D Physical Security 4

Different levels of physical security (protection against theft and vandalism) can be achieved through case design. The physical structure and shell of a case serves to isolate from the visitor the display contents; locking hardware discourages unofficial access yet facilitates authorized access.

Early in the design phase the level of security design and hardware should be selected; this includes appropriately resistant construction materials and glazing, and locking systems.

The designer should always consider the conceal-ment of all case screws and the use of tamper-resistant screws where visible.

Where warranted, electronic detection sensors should be installed.

Tamper Resistant Screws are available in a variety of head profiles and with different tool access styles. Machine screws need to fasten into threaded inserts, wood screws require a pre-drilled hole to prevent splitting of the material.

Phillips Snake Eyes Allen TORX

Locking Hardware is available to cover a wide variety of conditions and some manufactures provide security ratings for different levels of protection.

Pneumatic and Electronic Locks allow locking plungers and catches to be hidden within the case structure and operated remotely for locking and unlocking access doors and removable vitrines.

Camlock Dead Bolt Push Pin Twist lock Central locking system Electronic lock

3:E Map Structural Security 5

The degree of physical security offered by an exhibit case depends primarily on the materials used in the construction of its structure and shell. The specific level of resistance required of case materials is determined by an assessment of the security risks associated with an exhibit's particular circumstances.

In most instances standard case construction is adequate, however, there are circumstances when a higher degree of resistance is paramount. In the illustrations below a range of different materials are shown.

When used in combination these materials can meet the security needs of most exhibits.

1. Standard case construc-tion; wood substrate with a mitered corner.

2. Wood substrate with a mitered corner, reinforced with a metal angle

3. Ballistic resistant panel with a metal angle reinforcing the corner

5. One half inch thick "high hardened" steel in welded corner joint

4. Sheet metal rein-forced with a metal angle

Security Glass Generally consists of laminated layers of glass and/or polycarbonate. Different formulations can achieve different levels of physical and ballistic resistance. In ballistic applications a layer of polycarbonate is preferred on the inside of the display chamber to help reduce spaulling, (small glass fragments emitted when the glass is impacted).

3:F Electronic Security Sensors Map

The most widely used methods for electronic secu-rity are remote sensing and direct wired sensing.

Sensors are available for exhibit cases to cover a wide variety of security needs, for example:

• magnetic door and window sensors;

• motion detectors (infrared and passive infrared);

• glass break sensors (acoustic & shock);

• metal attack sensors;

• light level threshold sensors;

• heat and relative humidity threshold sensors;

• water and moisture sensors;

• laser beam/field sensors.

Remote Radio Frequency Transmitters can be installed within cases without a direct electrical connection.

Hard Wired Devices are installed within cases and are connected to a remote monitoring panel, alarm, or guard station.

Construction Materials

4:A Wood Construction

4:B Metal Construction

4:C Case Furniture

4:A Wood Construction

From a preservation perspective wood products are less stable and therefore are less desirable materials for use in the construction of a case's display and maintenance chambers.

When wood is required, it is advisable to: select less hazardous wood products and, isolate them with a vapor impermeable barrier.

Two isolation methods are available:

1. solid laminates- high pressure laminate (HPL) and plastic laminated foil (PLF), and;

2. specialized sealant coatings-…