Tag Archives: environmental monitoring

Environment, Preservation Week

Preservation Week 2025: A Day in the Life, Tuesday

1 Comment

Welcome to Day 2 of Preservation Week 2025! To see other posts in this series, follow these links:

Day 1: Curatorial meetings
Day 2: Presenting our HVAC pilot project
Day 3: Using UV light to analyze materials
Day 4: Discovering details in book bindings
Day 5: Field trip! Gathering damaged books from Circulation points

Last year, in response to the Duke Climate Commitment, we tested an overnight HVAC shutdown pilot project during the winter months in the circulating collections. We wanted to see if the University could reduce its carbon footprint while maintaining adequate environmental conditions our collections. We worked closely with Duke Facilities to determine how to implement this program. You might recall at the beginning of the project we placed an Onset HOBO MX1101 datalogger inside a discarded book to see how it responded to changes in temperature and humidity in the stacks during the HVAC shutdown project.

We noticed some curious readings and decided that the amount of hollowed-out material likely affected the way the text block reacted to changes in humidity and temperature. This winter we created a second test book but this time we used a probe-style Onset HOBO 2302 datalogger. Our working theory was that a smaller hole in the middle of the book would give us better data.

I grabbed a book from the discard pile and started cutting. Once I hollowed out a space for the probe, I created an Ethafoam plug to minimize air filtration at the fore edge.

Datalogger inside text block.

The books were placed side by side on the shelf with books on either side to ensure they stayed closed. This area of the stacks contain mobile shelving, which are opened and closed regularly as patrons use the aisle.

First test book (left) and the newer book are identified by their bright red wrapper.

I looked at the last 30 days of data from this datalogger in preparation for a talk about this project at the State Energy Conference today. You can see the old book (blue line) vs. the new book (green line) both react slowly to changing conditions. However, you can also clearly see the book with the smaller hole is reacting more slowly to changes in humidity (temperatures remain very stable).  Both books are slower to react to ambient rH conditions. But you can definitely see a difference between the two books, which I think is at least partially due to the amount of material excavated from the center of the book.

Environmental data from last 30 days

Tom Young, Critical Systems Controls Engineer in Duke Facilities Management, and I are excited to share our findings with the conference attendees today. Spoiler alert: the energy savings were substantial and the books are fine.

 

Environment

Peering Into the Unknown

Duke Libraries is not paid to advertise Onset products, we just really like them.

We all know how important a stable environment is for the long-term preservation of our collections. An environmental monitoring program is essential for collecting both short-term and long-trend data in critical areas of the library.

For many years now we have used Onset HOBO MX1101 dataloggers to monitor temperature and humidity conditions over long periods of time. These are bluetooth enabled, very accurate, and cost effective. We currently have about 30 of these monitors in a variety of locations around our library including our Exhibit Suite.

Meg installing HOBOs in the exhibit cases.

Last year we installed an Onset MX Gateway in the Exhibit Suite. This device allows us to look at data remotely from our desktop. It reads any HOBO within 100 feet of the Gateway, and uploads the data into the cloud. In fact, we get even more than 100 feet from our Gateway. It currently not only reads all the dataloggers in our exhibit suite, but three dataloggers outside the suite in the foyer, and three that are one level down in the Conservation and DPC labs.

Onset MX Gateway, MX1101 HOBO datalogger, and the Gateway interface.
Setting Up the Gateway and HOBO Dataloggers

The Gateway interface is fairly easy to use. If you set up your HOBOs correctly, assign them to groups, and are mindful of naming conventions, you can easily group related dataloggers together. This is helpful when you ask the Gateway to download reports.

A selection of HOBO dataloggers that can be seen by the Gateway.

Among the categories are Exhibit Cases (dataloggers inside the cases), Biddle Exhibit Suite (dataloggers in the various rooms in the suite), and the Labs (Conservation, Digital Production Center, and the Exhibits office). The Gateway allows you to set up dashboards to group similar dataloggers together.

A Portion of the Gateway dashboard for the Exhibit Suite. It turns out that the table the Perkins Lobby datalogger is attached to was moved and is now over a heating vent. We didn’t realize this until we logged into the dashboard. See how useful the Gateway is?
Expanding the Monitoring Program

This summer we are expanding our exhibit monitoring to include the Onset MX2202 LUX/Temp meters. These are going inside a few exhibit cases to monitor light levels (LUX) and temperature (F). We have a couple cases near internal windows, and several outside in the library foyer. Before we got the MX2202 monitors we could only do spot readings with our Elsec light meter. We can now understand what sort of cumulative light exposure these cases get throughout the year.

The Gateway dashboard for the MX2202 dataloggers.

Since the Gateway allows you to download the data into Excel, you can set up templates to do your data analysis. I’ve set up a template that includes the min/max/median/mode for both the LUX and temperature readings. The graph gives you a quick visual for the time period you requested in the Gateway report.

Draft analysis template for the LUX meters. The meter in the photo gallery cannot be reached by the Gateway, so we will have to download that datalogger individually and add the data to the spreadsheet for analysis. 

We have similar spreadsheets for the HOBOs in the Exhibit Suite that record temperature and relative humidity.  We download the environmental data by month, and look to see if any trends or concerns arise. The Gateway also allows you to look at the data in real time so we can view it weekly to catch any problems.

Look at those beautiful flat lines.

Until we installed the Gateway we had to go upstairs and download each HOBO individually with our phone or iPad. This is so much easier and more efficient.