Environmental controls should aim to maintain an environment that is not hospitable for pests. Environmental factors that can be controlled include; cleanliness, temperature, relative humidity and lighting. Ideally, your institution should strive to maintain environmental conditions that both discourage pests from being drawn into collections areas and from flourishing if they do enter.
Pests are not drawn to clean or tidy areas. They tend to enjoy spaces that are dark, damp, and have plenty of food sources or available nesting materials. Areas that go undisturbed by human activity are perfect homes for insects and rodents, so it is important to look beyond the spaces that house your collections and staff. Building voids such as utility spaces, hollow walls or access spaces can often be the source of an infestation. Getting these areas under control is crucial to keeping your museum or cultural center pest free. One institution found that a closed off area under some stairs had a build-up of dust and dead mice that became the perfect breeding ground for beetles and moths. Breaking open this area and cleaning out the years of debris solved problems they were experiencing in surrounding areas.
Custodial and housekeeping staff are the foot soldiers of the museum and they are crucial allies for your IPM program! Check out the Creating buy-in section for more information about how to engage the staff in your institution so that IPM.
For more information about the importance of house keeping see this video: Developing a housekeeping plan
Temperature: Most museums keep their collection housing and exhibition spaces at a temperature between 65 -70 degrees. Insect activity increases in higher temperatures which is why summer is such a busy season for Integrated Pest Management staff. Keeping the internal environment of your building cool and stable can help to deter insects from entering your space and decrease the breeding and eating patterns of any insects already inhabiting your collections and spaces. Keeping a stable environment is easier said than done, and many historic houses and museums have multiple micro-climates throughout the buildings. Not every area can be climate controlled, but it is important to understand the different environments around your building so that they can be monitored as “hot spots” for different ecosystems.
Relative Humidity: A relative humidity of 65% or above is ideal for mold growth and where there is mold, there is a tasty meal for fungi eating insects. Where there are small fungi eating insects, larger insects who enjoy proteinaceous snacks can gather. This can sometimes escalate quickly.
To learn how to manage a mold infestation check out this guide from the CCAHA
This guide from December 2019 shows RH monitors: CCAHA Environmental Data Collection
HVAC Systems: HVAC systems are critical for maintaining temperatures and stable relative humidity levels. If this system is not monitored through your department it can be helpful to collaborate with the team who does manage the HVAC system.
To purchase a guide that outlines best practices for HVAC use see ASHRAE 2019, Chapter 24 MGAL
Lighting: Many insects are drawn to lights. Lighting placement is an important consideration for IPM staff around building entry points. Lights can draw insects into buildings. On the flip side, lights can be used as a method for prevention. In areas that are inevitable lures for insects – such as trash collection spaces – it can be useful to install UV light traps so that populations can be kept under control rather than breeding in and around these areas that are often difficult to monitor and clean.
Our friends over at Insects Limited have information about lights and something for all of your lighting needs! Insects Limited lighting guide
This information on lighting is another good educational resource to learn about lights.
Office Environments: Keeping offices food and plant free is essential to preventing pest friendly environments. This is a difficult policy to implement because it involves asking people to change their habits and behavior but more information can be found on the Creating Buy in page.
The IPM-WG has created two template documents that can be used to create procedure documents specificly geared to your institution. One focuses on the control of climate and water sources, and the other on housekeeping procedures.