HUMIDITY AND THE NEW CARRIAGE MUSEUM AT THE MUSEUMS AT STONY BROOK    11 Dec 90
AIC 1990 Paper for Wood Artifacts Update S...
Submitted to:
    Steve Pine, Chair, Wood Artifacts Update Session; PO Box 13157, Houston, TX
        77219; (713) 529-877...
BACKGROUND
----------

Under supervision of the curator, planning for the new museum project for the
Stony Brook carriage ...
remove moisture) and temperature (add and remove heat), filter the air (remove
particulates and offending gasses), and per...
some time since the head-end failure in July of 1988), providing local control
of the individual compressors, and modulati...
Although other issues were raised, the issues described here are confined to
the major damage which could be associated wi...
damage to the collection.

HUMIDITY. The Fine Objects Conservation report from September 1987 makes
specific reference to ...
the week of 9 February 1989 for the "To Ride Upon A Coach" and "Fire Fighting."

TYPICAL UNHEATED SHED CONDITIONS. Based o...
The boiler cut-out is typical of a system startup problem in new construction;
however, this is a chronic problem at the M...
HVAC failure and low humidity. The humidity environment was further
complicated by the daily heat gain from the lighting, ...
stabilize for a period of time before collection move-in to allow
       identification of any start-up problems, and to a...
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AIC Stony Brook New Carriage Museum Paper (Stony1C.Txt)

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HUMIDITY AND THE NEW CARRIAGE MUSEUM AT THE MUSEUMS AT STONY BROOK

AIC 1990 Paper for Wood Artifacts Update Session

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AIC Stony Brook New Carriage Museum Paper (Stony1C.Txt)

  1. 1. HUMIDITY AND THE NEW CARRIAGE MUSEUM AT THE MUSEUMS AT STONY BROOK 11 Dec 90 AIC 1990 Paper for Wood Artifacts Update Session - Final Draft -------------------------------------------------------------------------------- HUMIDITY AND THE NEW CARRIAGE MUSEUM AT THE MUSEUMS AT STONY BROOK ------------------------------------------------------------------- ABSTRACT: The new Carriage Museum at The Museums at Stony Brook represents several successes as well as lessons for improvement in providing an effective conservation environment for a carriage collection. The most important aspect to the experience is the humidity sensitivity characterized for the wood carriages, and general precautions to protect the collection in the course of new construction. Previous to the new museum, the carriage collection had acclimated to the relatively moist, unheated conditions, characteristic of the current storage sheds and the old museum. In the course of the new museum project, the collection was exposed to periods of moderately low humidity which are presumed to have caused damage to the collection. These low humidity events came from not allowing the new museum environment to stabilize for several months before moving the collection in, and unhappy coincidences that lead to chronic poor reliability of an otherwise effective steam humidification system. There is considerable evidence to characterize the humidity problems. The pre- and post-move condition of the collection were photographed, and were accessed by the consulting conservator who does regular work on the collection. There were some humidity records for move-in humidity conditions in 1987, and museum- wide hygrothermographs for chronic humidity problems in 1989. Hygrothermographs have also been made for the typical unheated shed condition. Several observations are offered on the general humidity sensitivity of carriages as wood artifacts. The most important is that damage came from short-term moderately low humidity events, generally only around 30-35% RH, much higher than the typical 15-20% RH thought as most damaging for short periods. Several planned measures to improve humidification reliability at the Carriage Museum are described. The moving of the collection into the museum before construction was finished also exposed the collection to construction activities. Guidelines for managing and protecting a collection in the course of a museum construction project are suggested. Prepared by: William P. Lull, Principal, Garrison/Lull, PO Box 337, Princeton Junction, NJ 08550, (609) 259-8050; Merri Ferrell, Curator of Carriages, Carriage Museum, The Museums at Stony Brook; and, Linda Merk-Gould, Fine Objects Conservation. Reviewed by: Deborah Johnson, Director of Curatorial Affairs and Art Curator, The Museums at Stony Brook.
  2. 2. Submitted to: Steve Pine, Chair, Wood Artifacts Update Session; PO Box 13157, Houston, TX 77219; (713) 529-8773. Contents: Introduction . . . . . . . . . . . . . . . . . . . . . . 2 Background . . . . . . . . . . . . . . . . . . . . . . . 3 Description of the New Carriage Museum . . . . . . . . . 3 General/Architectural . . . . . . . . . . . . . . . 3 HVAC/Mechanical . . . . . . . . . . . . . . . . . . 3 Lighting/Electrical . . . . . . . . . . . . . . . . 5 Records and Documentation . . . . . . . . . . . . . 5 Resulting Quality of the Conservation Environment . . . 5 Observed Collection Problems . . . . . . . . . . . . 6 Mechanisms of Damage . . . . . . . . . . . . . . . . 6 Identified Humidity Problems and Action Planned . . 8 Related Problems at Another Carriage Museum . . . . . . 9 Summary . . . . . . . . . . . . . . . . . . . . . . . . 10 INTRODUCTION ------------ Previous to the new museum, the carriage collection had been kept in the old unheated museum, and in unheated sheds. This is also characteristic of the environments the collection would have seen historically. The collection had acclimated to the "unheated" ambient conditions, where humidities generally range from 50 to 90%RH. The New Carriage Museum was intended to provide a modern exhibit environment to safely display the collection under better exhibit conditions, and improve year-round visitor comfort. In the course of the New Museum project, the importance of special precautions to protect a carriage collection from low humidities and construction was demonstrated. Carriages are composite objects comprised of a variety of materials. The primary structure is wood, used for parts of framing and panels for the body and reaches, spring blocks, and wheels for the under-carriage. To reduce the weight of the vehicles, the body panels are usually made of broad sheets of thin poplar; these panels are particularly sensitive to low humidity. Steam bending and other forms of structural alteration of the panels contributes to their sensitivity to low humidity. Other materials found in carriages are base metals (steel and malleable cast iron), used for structural reenforcement such as braces and reach plates; secondary ornamental metal such as silver and brass for brightwork and handles; textiles, ivory, enamelled cloth, and leather. Although high humidity may contribute to problems such as mold growth, tarnish or rust, these conditions are less severe than the problems of irreversible structural damage to the wood components from low humidity. [Slides available illustrating carriage conservation issues and before/after conditions of conservation.]
  3. 3. BACKGROUND ---------- Under supervision of the curator, planning for the new museum project for the Stony Brook carriage collection started in 1982, starting a five year program which resulted in completion of construction in 1987. The carriage collection was removed from the old carriage museum, and stored in unheated shed conditions, allowing the new Carriage Museum to be constructed on roughly the same site as the old carriage museum in 1986-87. The collection was photographed for publications on the collection, and moved from the temporary storage and into the new museum in April and May of 1987, during the final completion of interior finish construction. For the next two years, consulting conservators made regular inspections and evaluations of the collection. In 1989, services of a collections environment consultant were retained to investigate the possible building systems causes for the damage coincident with the move into the new museum, and to recommend possible solutions. DESCRIPTION OF THE NEW CARRIAGE MUSEUM -------------------------------------- The following describes the major aspects of the design of the New Carriage Museum at Stony Brook. GENERAL/ARCHITECTURAL The new Carriage Museum is a two-level structure of roughly 40,000 square feet. The structural system is a combination of metal framing, poured concrete, cement block and precast concrete planks. The roof structure is a combination of metal framing, metal decking, and wood sheathing. With an exterior wood clapboard finish and wood frame vertical sash windows, the museum building imitates the wood construction of earlier barns and houses of the area and other existing buildings on the museum grounds. In several instances, windows have been located on the exterior for effect, but they do not penetrate to the inside in collection/exhibition areas. The roof is composed of sloped shingled mansards, usually with a flat built-up roof beyond. The lower level extends below grade, with part below an exposed outdoor patio area. The site water drainage design is reported to provide below-grade water drainage to below the lowest finished floor. [Slides available illustrating general exterior and interior construction.] HUMIDITY TOLERANT ENVELOPE. The design documents show the use of exposed metal pans, internal vapor barriers and exterior vapor barriers throughout, which should provide a humidity-tolerant envelope. The execution of the vapor barriers and various thermal conditions could not be confirmed without destructive testing. There have been problems with condensation on cold internal surfaces where the inside surface reached dew-point, evidently due to inadequate insulation or thermal design. HVAC/MECHANICAL These systems are the main determinants for actively maintaining the conservation environment. The purpose of the heating, ventilating and air conditioning (HVAC) system is to establish and maintain humidity (add and
  4. 4. remove moisture) and temperature (add and remove heat), filter the air (remove particulates and offending gasses), and perform these tasks evenly throughout the space. The system must also do these things reliably, to provide a stable environment for the collection. AIR HANDLING UNITS: SINGLE-ZONE WITH REHEAT AND HUMIDIFICATION. The Museum is served by twelve (12) independent constant-volume direct-expansion (DX) single- zone air handling systems, with common hot water heat/reheat and steam humidification. Each air handling system is a draw-through DX split-system, located near the spaces served, having its own separate compressor and condenser, located on the roof. In the case of the larger 10-ton systems, the compressors are duplex, allowing 50%/50% staged cooling. The systems do not have air economizers; minimum outside air is introduced through two of the air- handling systems. [Slides available showing HVAC system.] This can be a first-class all-air system for conservation goals, which locates virtually all of the service and repair operations in the fan room or on the roof, and requires no HVAC piping in the spaces served, yet provides full capabilities in environmental temperature and humidity control. Supply air is delivered to the space by exposed ducts and exposed flared rectangular 4-way diffusers, located about two feet below the structural ceiling; and by longer 2-way rectangular bar diffusers in the bottom and sides of bulkheads, and in high sidewall applications. COOLING. The multiple compressors, one or more per system, provide independent reliability. The systems use DX cooling, which has refrigerant piping instead of water piping, reducing the potential damage to the collection from piping leaks. HEAT/REHEAT. Space heating and dehumidification reheat are provided from a central hot water boiler. Each air handling system has a hot water coil in the reheat position. This coil provides both heating and reheat, and is controlled with a three-way valve. The central hot water boiler maintains the heating water loop temperature, firing on demand, and is reported not to have seasonal shutdown, making heating water available during all seasons for dehumidification reheat. While there is little piping directly in the collection spaces, there is piping to each of the fan rooms. HUMIDIFICATION. The systems are also served by a common humidification steam system, from a central steam boiler, feeding local in-duct steam humidifiers through copper piping. There is no use of boiler water treatment compounds reported, and the boiler is reported to be blown-down daily. Humidification provided with clean steam through in-duct steam manifolds should provide good control. While there is little piping directly in the collection spaces, there is piping to each of the humidifiers in or near the fan rooms. Steam can cause over-humidification when a control system fails, and the untreated water may shorten the life of the steam distribution piping. [Slides available showing diffusers, boilers and humidifiers.] CONTROLS. The control system uses a rudimentary local-panel direct digital control (DDC) system. Although they can be controlled and monitored from a central head-end computer, these can operate independently (as they have for
  5. 5. some time since the head-end failure in July of 1988), providing local control of the individual compressors, and modulation of the humidification steam and heating water at the unit. Local panels monitor space conditions with electronic humidity and temperature sensors, and modulate equipment with relays or electric motors. (Pneumatic controls or operators are not used.) LIGHTING/ELECTRICAL The Museum exhibit areas are lit with 120v track lights. Most fixtures are standard-base R- or PAR-lamp fixtures. A few fixtures are quartz-iodine (tungsten-halogen) flood lights. Three-point lighting (key, back and fill) treatment for display is was not used in the original design, which lead to initial over-lighting of the displays to attempt to show more detail. RECORDS AND DOCUMENTATION The Carriage Museum facilities staff maintains a very good set of information on the building systems, and is able to locate such information better than the majority of similar institutions. The Museum has developed a very good program of documenting the environment and condition of the collection. The considerable data developed during the first two years of operation of the new Carriage Museum was invaluable in tracking the environment, and condition of the collection. The ongoing use of standardized facility and collection damage reports help to fix the time and character of problems and damage, and the Museum has been effective in getting the general staff, particularly the guards, to fill out these reports. The regular use of multiple hygrothermographs was of considerable value in identifying and isolating the humidity conditions and problems. A building- wide concurrent problem was easily identified only through the availability of multiple charts. The charts also allowed quick identification of the abnormal operation of the "Fire Fighting" Gallery, when compared to other galleries over the same time period. RESULTING QUALITY OF THE CONSERVATION ENVIRONMENT -------------------------------------------------- The new Carriage Museum at the Museums at Stony Brook is intended to provide a safe environment for the carriage collection. To a large extent this is achieved through the elimination of windows in the exhibit areas, use of steam humidification, use of a relatively independent heating, ventilating and air conditioning (HVAC) system treatment, and the humidity tolerant design of the building envelope. Unfortunately, the new museum falls short in several aspects, primarily in providing a reliable level of humidity that is consistent with the unheated sheds, where the collection had previously spent most of its life. The following environmental evaluation observations, discussions and conclusions are made with the benefits of reports prepared by Ms. Linda Merk- Gould of Fine Objects Conservation, and Mr. Paul Himmelstein and Ms. Barbara Appelbaum of Appelbaum and Himmelstein, and from discussions of the museum on 13 July 1989 at the offices of Appelbaum and Himmelstein.
  6. 6. Although other issues were raised, the issues described here are confined to the major damage which could be associated with humidity and humidity-related problems. Other problems with the new museum, such as the use of an outside patio as a roof for a collection space, general weather leaks and condensation, inadequate particulate control, basic space layout inefficiency (causing inefficient collection handling), weak exhibit design and lighting developed by outside consultants (which caused an initial tendency to over-light the collection), are not discussed. OBSERVED COLLECTION PROBLEMS [Slides available for selected problems.] In general, damage was already noted approximately 5 months after move-in, in the observations in the Fine Objects Conservation report dated September 1987, which specifically addressed itself to damage to the collection since moving into the new museum. That report noted: "cracks radiating [from older damage]," "crack just beginning in the wood," "new crack in the right side," "panel is separating from the support molding," "leather top is shrinking, breaking and separating," "split in the leather right side panel," "boot cover (enameled canvas) is dramatically shrinking," "new tears in the leather," "new tear in the leather back curtain...is increasing," "fresh crack," "the paint is continuing to flake," "wood substrate is shrinking - causing the gold surface to tent," "wood...is cracking," "numerous new cracks with accompanying paint losses," "loose paint flecks," "lifting paint," "window has two breaks," "numerous cracks," "wood shrinkage and associated paint loss," "crack beginning to occur," and "metal is corroding." It should be noted that these observations by Ms. Merk-Gould are with the benefit of her working with the collection since 1984. She was thus familiar with older damage, and able to note the recent problems from familiarity as well as straight observations. The older damage suffered by the collection was minimal when compared to the damage since relocation to the new museum building. CRACKING AND CHECKING. There was obvious damage to the collection in the form of cracking, checking and splitting of the wood. Based on photographs and condition reports on the collection before and after the move into the new museum, much of this was acute recent damage, concurrent with the first few months after the move into the new museum. There also appeared to be ongoing damage to the collection of this character. FINISH DELAMINATION AND FLAKING. There were numerous observations of paint flaking from wood and from corroded and rusted metal. The losses of paint and surface finishes come as a consequence of the low-humidity shrinkage of wood. In some instances the air flow from the HVAC system has blown finish flakes off their original surface, complicating the task of conservation. "Breezes" are noticeable as one walks through the building, particularly in the lower level galleries. MECHANISMS OF DAMAGE The following humidity-related mechanisms are suspected as causing the observed
  7. 7. damage to the collection. HUMIDITY. The Fine Objects Conservation report from September 1987 makes specific reference to damage due to "the humidity being too low or the vehicle not introduced slowly enough to the new environment," and "the split in the leather...is due to shrinkage caused by too low temperature-humidity environment." For some carriages the report specifically recommends "a controlled increase in humidity may prevent further damage," and that further damage will occur unless "the humidity is raised." It summarizes that "the majority of this damage can be attributed to a severe change in temperature and humidity." The subsequent report from February 1989 notes "incipient cracking...caused by dehydration of the wood," several citations of damage from "low relative humidity," and other examples of continuing low humidity damage. This clearly indicates a chronic problem. The February 1988 condition survey by Fine Objects Conservation cites "unstable environment" and "wide fluctuation in the environment including extreme dryness" as problems. Concerning humidity, the August 1989 report by Fine Objects Conservation notes "the collection is in a wood-cracking-shock trying to adjust to the ongoing fluctuations," and "the RH fluctuates between 35-60% throughout most of the New Museum and those carriages have severe new cracks in the wood." The 21 March 1988 report by Appelbaum and Himmelstein notes that "the carriages show significant damage very quickly when the RH drops." CHARACTER OF LOW HUMIDITY EXPOSURES TO THE COLLECTION. As noted in the Museum records, the carriages were moved into the new museum from 2 April to 21 May 1987. The hygrothermographs taken the week of 15 April 1987 note considerable fluctuations in humidity. While the graph shows humidity between 45% and 100% RH, the 100% RH extremes show extended periods (in some cases over 24 hours) of "clipping" at 100% RH, which is uncharacteristic of high humidity shown on other hygrothermograph charts. The recent ambient humidity charts from the unconditioned storage sheds show only brief peaks to 100% RH during rainy periods. This indicates that the hygrothermographs taken the week of 15 April 1987 were likely out of calibration, reading too high by 20% to 30% RH. This means that the collection was exposed to lows of not 45% RH, but of at least 25% RH. This is also consistent with reports that space heaters were used that cool spring to warm the building when the HVAC system was not fully operational - these would certainly drop the humidity to low levels. In addition to reports of new damage to the collection, museum records note "fluctuations of 40%" in RH for the week of 12 May 1987. Throughout the summer of 1987 continuing damage to the collection was noted by the museum. Before failure of the monitoring "head end" of the HVAC controls system in July of 1988, there were regular daily records available from the system of humidity (although daily readings were not always recorded). On 22 February 1988, when the collection was in the new museum under winter conditions with the potential damage from dry winter heat, the humidity dropped throughout the museum to readings of 30% to 40% RH for several days, and then returned to the typical readings of 54% to 63% RH. This period of extended low humidity was at least down to 30% RH, as read from control system sensors. This event was also noted at the time to be coincident with the steam boiler failure. Hygrothermographs from the beginning of 1989 show humidity generally maintained between 45% RH and 60% RH, but regular coincident drops in humidity throughout the museum. These drops generally occur at least once every two weeks, can extend for several days, are characteristic of a system-wide failure of humidification capability, and are coincident with reports of steam boiler failures. These events can drop by 35% RH to reach lows of 30% RH, as shown
  8. 8. the week of 9 February 1989 for the "To Ride Upon A Coach" and "Fire Fighting." TYPICAL UNHEATED SHED CONDITIONS. Based on the 1989 hygrothermographs from the storage sheds, which are presumed to be typical, the humidity regularly fluctuates from 40% to 100% in the unconditioned spaces, never falling below 50% for more than 12 hours. The clear evidence of exposure of the collection to low humidities for extended periods shows the collection was and is subject to unprecedented dry conditions in the new museum. As concluded by the conservators, this can primarily explain the majority of the damage to the collection. LIGHT. Over-lighting is noted in the 3 September 1987 and 13 December 1987 reports by Fine Objects Conservation: "the lights shining directly on the side are accelerating the deterioration," "crack is wider probably from the light shining directly on that spot." Light levels as high as 200 footcandles were noted in reports. Other than damage from the light itself, the high light levels may cause a micro-climate of spot heating, drying and desiccation, in spite of any average humidity maintained by the HVAC system. The lighting problem was addressed through re-lighting of the exhibits in 1988, and lighting is now at or near conservation goals. AIR VELOCITY. The February 1988 condition survey and August 1989 report by Fine Objects Conservation cite "extreme air flow [velocity]" as a problem. At the 13 July meeting it was noted that the Coupe (#53) was in obvious air flow and seemed to have more cracks than other objects in the same space. Mr. Himmelstein speculated that the air velocity might cause surface evaporation, and drying. SUPPLY AIR. The discharge of improperly diffused supply air (at supply air conditions rather than room conditions) may expose the collection to extremes in temperature and humidity as the supply air is warmed, cooled, humidified and dehumidified. Not only would this trigger the same humidity/temperature damage mentioned earlier, but for the less massive parts of the collection these rapid swings might cause accelerated stress. In some instances, such as warm air followed by cool air, moisture might be removed from the object as the air temperature cycles. One Fine Objects Conservation report cites "supply air vent directly above...a cool draft can be felt when standing near the vehicle." IDENTIFIED HUMIDITY PROBLEMS AND ACTION PLANNED There are several problem evident in the building systems. The following pertain to the quality and reliability of the humidity environment. HUMIDITY AND STEAM BOILER CUT-OUT. The primary current problem is the reliability of the steam humidification system. This is evidenced by regular excursions in low humidity in fall, winter and spring, due to cut-out of the central steam humidification boiler, reportedly due to the common brief loss of electric mains power. This is evident in the multiple hygrothermographs as a common building-wide humidity signature indicating loss in humidification, which occurs at least once or twice each month in the heating season. When the boiler stops, it requires manual reset to be placed back on line. A primary problem with resetting the boiler is its penthouse location, making access inconvenient and risky in inclement weather.
  9. 9. The boiler cut-out is typical of a system startup problem in new construction; however, this is a chronic problem at the Museum. This is due, in part, to the unhappy coincidence of a steam boiler with a code-required electric hookup which is intolerant of mains power dropouts, connected to a particular Long Island Lighting Company power grid which is prone to power dropouts. Since the steam boiler is the only piece of equipment evidently sensitive to this problem, a relatively straight-forward solution is to install a small battery-powered uninterruptable power system (UPS) to allow the boiler electric auxiliaries to span the brief power outages. Further system reliability can be achieved through augmenting the HVAC controls system to provide "fail-safe" humidity interrupt of heating, preventing heating (and thus low humidity) whenever humidity drops below 50% RH, and/or when humidification steam pressure is lost. RUN-AWAY HUMIDIFICATION. Some time ago an electric operator failed on one of the humidifiers serving the upper level. This caused run-away humidification, leading to in-duct condensation, water damage to the ceiling, and water damage to the carriage below. The operator was replaced, but a similar failure would likely result in the same damage scenario, unless corrective action was immediately taken. Since runaway humidification is a common problem in humidified environments, a high-limit humidity control is being considered. A second "high-limit" humidistat, or a high-humidity signal from redundant space humidity sensors for each humidified zone could deactivate the humidifier when humidity exceeds the setpoint selected between 60% and 85% RH. RELATED PROBLEMS AT ANOTHER CARRIAGE MUSEUM -------------------------------------------- Mr. Bill Cooke, Director of the Kentucky Horse Park Museum, relates similar observations on the sensitivity of a carriage collection to moderately low humidity. In their carriage room, built around 1984, they intended to provide a "safer" inside controlled environment, anticipating the rationale of the Museums at Stony Brook. Dust and humidity control systems were installed, with contractor promises of humidity control to a +/-3% RH tolerance at 50 to 55% RH. The project was "fast tracked," where construction began before the full design was complete. Before the new carriage room, the Kentucky Horse Park Museum carriage collection was kept in unheated barns. Mr. Cooke observed that, in the barns, the collection held up excellently, except for the expected bird and rodent problems. The major structure and panels of the carriages were in fine shape. Upon moving into the new environment, some minor cracks were observed, but no major problems. The HVAC system was not performing to specification, but was generally keeping the humidity somewhere near the 50% RH goal, although its operation was far from stable or satisfactory. A major prolonged HVAC system failure, presumably of the humidification system, occurred one spring, coincident with a cold snap in the weather. This lead to an abrupt drop in humidity of about 20%, from the around the 50's to the 30's in RH. Major splitting of the collection ensued, with the first damage observed after about a day and a half at prolonged exposure to the moderately lower humidity. Damage was definitely evident after a week of the continued
  10. 10. HVAC failure and low humidity. The humidity environment was further complicated by the daily heat gain from the lighting, which induced further humidity fluctuations. SUMMARY ------- The lessons to be learned from the Carriage Museum experience are: 1. HUMIDITY SENSITIVITY. The Stony Brook collection fared well for decades in the sheds where humidity typically cycles from 50 to 100% RH, but never falls lower for more than a few hours. Wood carriages are evidently prone to damage from short-term moderately low humidity events, generally only around 30-35% RH, much higher than the typical 15-20% RH thought as most damaging for short periods. This suggests that the outdoor-acclimated carriages are particularly and critically sensitive to moderately low humidities for even relatively brief periods, or are particularly sensitive to humidity swings between 35% to 60% over a few days. This indicates extraordinary precautions are required to prevent a carriage collection from being exposed to moderately low humidity for any more than a few hours. In contrast, the carriages are relatively tolerant of high humidities as are typical for an unheated shed. 2. HUMIDIFICATION RELIABILITY. The critical aspect to a carriage environment is to avoid any chance of a humidity below 40-50% RH, which indicates the critical need for a reliable humidification system. Above all other considerations, including temperature, the relative humidity not fall below 50% RH. Although a museum may appear to have adequate humidification, it may fail to operate consistently to provide the required moisture. 3. LOW LEVEL LIGHTING. Due to possible overheating and resulting micro- climates and spot desiccation, lighting must always be at conservation light levels. Where possible, the lighting should be with lamps that have dichroic filters or low infra-red (IR) output, and fixtures which have better control of the light to prevent overlighting. 4. DELAY MOVE-IN. There are many aspects to a newly constructed building which would indicate a considerable delay between "completion" and move-in of the collection. The threats include roof leaks (which are common and usually easily repaired), inoperative or unstable environmental control systems, off-gassing from construction materials, untested lighting, and the preponderance of construction workers, on whom the value and sensitivity of a carriage collection is often lost. Consider the following guidelines for a proper delay before moving a collection into a new space: a) New collection spaces should be completely finished, with absolutely all construction trades finished before considering moving in the collection. Although it should be completely avoided, if untrained personnel must work near the collection, considerable care and constant monitoring of such activity is required. b) A new collection space should be allowed to "off-gas" for a period of time before collection move-in to prevent solvent damage to the collection. c) A new HVAC system serving a collection space should be allowed to
  11. 11. stabilize for a period of time before collection move-in to allow identification of any start-up problems, and to allow the system to aid in the removal of construction moisture and off-gassing compounds. A recording hygrothermograph should be used to confirm that the system is providing the desired environment for an extended period, several weeks, preferably over heating, cooling, humidification and dehumidification conditions, before moving in the collection. d) Before collection move-in, a new collection space should be closely monitored for construction problems, such as roof leaks, piping leaks, condensation, and other possible threats to the collection, and prompt corrective action should be taken. Corrective actions should be completed and confirmed as effective, not merely scheduled, before setting a firm move-in date for the collection. e) Any new lighting system should be installed and tested in typical configurations to identify mounting locations, distances and angles which will and will not provide illumination at conservation light levels, checked with a light meter. PROJECT SPECIFICS: The Carriage Museum -------------------------------------- Location: The Museums at Stony Brook, Stony Brook, New York Gross Size: 40,000 total square feet, over two levels. Collection Spaces: Galleries - 35,766 square feet Library Area - 738 square feet Support Areas - 3,496 square feet HVAC Systems: (12) Split-System DX Package Systems: 3 Tons, 1,760 cfm, (AHU3); serves: Fire Fighting (HT) 5 Tons, 2,400 cfm, (AHU1); serves: Coachman (HT) 5 Tons, 2,200 cfm, (AHU2); serves: Gypsy Wagon/Kid's Vehicles 7.5 Tons*, 4,000 cfm, (AHU4); serves: Carriages in Industrial Am (HT) 7.5 Tons*, 2,400 cfm, (AHU5); serves: Pleasure Driving (HT) 7.5 Tons, 3,000 cfm, (AHU6); serves: To Ride Upon a Coach (HT) 10 Tons*, 4,400 cfm, (AHU7); serves: Meeting Room 4 Tons, 1,600 cfm, (AHU8); serves: Lobby 7.5 Tons*, 3,000 cfm, (AHU9); serves: Grace Darling 7.5 Tons*, 3,000 cfm, (AHU10); serves: Catalyst (HT) 7.5 Tons*, 2,900 cfm, (AHU11); serves: European/Library/Shop 3 Tons*, 1,200 cfm, (AHU12); serves: European/Library/Shop * = Two-stage system; (HT) = Hygrothermograph monitored Current Filtration: 25% ASHRAE Dust Spot 80% ASHRAE Weight Arrestance Steam Boiler: 335,000 BTU/Hr (for humidification) Hot Water Boiler: 737,100 BTU/Hr (for space heating and reheat)

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