What is “preventive conservation?”
Preventive conservation is an umbrella term within the preservation world that describes actions meant to prevent damage to cultural heritage, or at least reduce the likelihood of damage (Caple 2012). Preventive conservation typically does not involve physical modification of an object. Rather, it addresses external factors like environmental conditions or how an item is handled.
Preventive conservation acts on a large scale – it deals with whole collections of objects instead of individual ones. This large scope makes preventive conservation the most efficient means of preservation!
Most preventive conservation practices combat the ten agents of deterioration. Examples of preventive conservation activities include creating and managing preservation environments (through environmental monitoring, building level climate control, and storage and display microclimates), preventing pest damage through integrated pest management, safe object handling, selecting sound storage, packing and display materials, fabricating supportive mounts that help, don’t hurt, artwork on exhibit, and emergency preparedness and response.
Who does preventive conservation?
Preventive conservation is now a whole sub-discipline of conservation and collections care. While there are conservators who specialize in preventive conservation, many collections care professionals with other job titles and backgrounds undertake preventive work every day, just as they have done historically. The history of preventive conservation is an expansive topic. If you’re interested in a deep dive, we’ve listed a few excellent resources below.
Early approaches (preventive conservation before the term existed)
Humans have long sought to safeguard valued items from damage and decay by identifying factors that exacerbate deterioration. Archaeological finds from prehistoric societies worldwide show evidence of repair, indicating a desire to prolong the use of both utilitarian and more special items. Ancient Roman authors recognized threats from multiple agents of deterioration. Pliny the Elder advised on how to deter pests from damaging wooden objects (fabricate them from bitter tasting cypress wood) and papyrus (treat it with citrus oil) (Caple 2012). The writings of other Roman era authors like Seneca and Pausanias demonstrated an accurate understanding of how light and humidity could negatively affect ivory, wood, metal and painted surfaces (Caple 2012).
Medieval practitioners of what we could now call preventive conservation used simple but effective measures to protect artwork and valued belongings.
Things like shutters and curtains on paintings and tightly sealed containers safeguarded art and personal possessions from light, pests, changes in temperature and humidity, and physical forces (Caple 2012).
Families in Europe passed along housekeeping manuals like that of Susanna Whatman to maintain preservation knowledge based on empirical observations. Whatman’s 18th century notebook contained instructions for a variety of housekeeping tasks and included recommendations on how to reduce damage caused by light, handling, and water. Generations of family members shared the manual, which contained such valuable advice that it was eventually published in 1952 (Staniforth 2013).
Twentieth century roots of preventive conservation
Between the sixteenth and nineteenth centuries, the institution of the museum evolved from private or courtly wunderkammer (“cabinet of curiosities”) collections to the more public, sometimes state-sponsored repositories with which we are familiar today. Over the course of the twentieth century, the concept of preventive conservation took shape as museum collection caretakers gained more sophisticated scientific tools and an improved understanding of the effects of environmental agents. Professionalization of the conservation and collections care fields during these decades also supported the development of preventive conservation. In the early twentieth century, new building technology allowed museums and other collections to exert more control over ambient temperature and humidity.
Experiences like the relocation of the British National Gallery’s collection to a very climate stable Welsh quarry during WWII drove home how significantly environmental agents could affect condition.
The establishment of academic training programs by the 1970s bolstered the numbers of professional staff with preventive conservation knowledge (Caple 2012).
The Museum Environment
In the late 1970’s, Garry Thomson wrote The Museum Environment, published in 1978 and revised in 1986. This seminal book highlighted preventive conservation and presented environmental parameters as essential tools for conservation and collections care (Hatchfield 2011).
The Museum Environment played a key role in popularizing the concept of preventive conservation within the wider museum community.
Based on works like this and the mid-century research that preceded it, museums adopted (and later debated, more on that soon) light, temperature and relative humidity standards.
Many of the principles that inform contemporary preventive conservation emerged in the 1990s (Caple 2012). Key texts, such as 1995’s Natural History Collections: A Preventive Conservation Approach, provided guidance on additional aspects of preventive care. Spearheaded by preventive conservation pioneer Carolyn Rose, this book demonstrated how preventive principles could be widely applied to non-art collections (Rose, Hawks and Waller 2019). Authors like Stefan Michalski and Robert Waller advocated using a risk management approach to the evaluation of collection threats, establishing
“a far more holistic and realistic approach to the subject of preventive conservation” (Caple 2012: 17).
In the mid-nineties, Waller and colleagues at the Canadian Conservation Institute codified the 10 Agents of Deterioration. We at Conserv, along with countless other institutions and preservation educators, continue to use this framework to think about collection risks.
NAGPRA – Today
The 1990’s also witnessed NAGPRA (Native American Graves Protection and Repatriation Act) legislation in the United States. NAGPRA helped spark an ongoing shift in collections care – and by extension preventive conservation – towards a more nuanced and inclusive philosophy.
This mindset recognizes the layered values, meanings, and relationships embodied by museum collections, taking into account factors beyond pure physical preservation.
Instead of limiting access and discouraging use, the traditional preventive conservation stance, an increasing number of institutions now invite people with ties to collections to handle, study and make decisions about objects important to them (Balachandran and McHugh 2019). Today’s holistic, yet individualized, preventive conservation practice weaves all of these threads together. Looking forward, new computing and analytical technology promises to expand our preservation toolkit, and ongoing reevaluation of values and assumptions promises to spur more evolution.
Balachandran S. and K. McHugh. 2019. Respectful and responsible stewardship: Maintaining and renewing the cultural relevance of museum collections. In Preventive Conservation: Collection Storage, ed. L. Elkin and C. Norris, 3-24.. New York: Society for the Preservation of Natural History ; American Institute for Conservation of Historic and Artistic Works; Smithsonian Institution; The George Washington University Museum Studies Program.
Caple, C. 2012. Preventive conservation in museums. Leicester readers in museum studies. Oxford: Routledge.
Hatchfield, P. 2011. Crack Warp Shrink Flake. Museum, January/February.
Rose, C., C. Hawks, and R. Waller. 2019. A preventive conservation approach to the storage of collections. In Preventive Conservation: Collection Storage, ed. L. Elkin and C. Norris, 43-55. New York: Society for the Preservation of Natural History ; American Institute for Conservation of Historic and Artistic Works; Smithsonian Institution; The George Washington University Museum Studies Program.
Staniforth, S, ed. 2013. Historical Perspectives on Preventive Conservation. Readings in Conservation. Los Angeles: Getty Conservation Institute.