What is PEMdata?
Why the web? Why not use application software on my local computer?
What does the name ‘PEMdata’ refer to?
How does PEMdata work?
What kind of data can be uploaded to PEMdata?
What is the best way to collect data for uploading to PEMdata?
Does PEMdata have special features for museums and libraries?
Does PEMdata have special features for HVAC management?
What kinds of graphs can I see in PEMdata?
What kinds of statistics can I see in PEMdata?
What do the acronyms on the Graphs and Statistics pages mean?
Do I have to register? Do I have to pay?
Is PEMdata secure?
What is the privacy policy?
Can I share my data on PEMdata with others?
Can I have multiple PEMdata accounts?
How do I name my datasets?
How do I rename or change the name of a dataset?
What is the difference between naming the dataset on PEMdata.com and assigning a location name with a command file?

PEMdata is a web resource for storing and analyzing temperature and humidity data. PEMdata was created by the Image Permanence Institute to help libraries, archives, and museums monitor their storage environments, by providing a way to organize, interpret, and share temperature and humidity data. PEMdata’s powerful analysis tools are designed to assist cultural institutions with the stewardship of their collections. For example, the Preservation Metrics can predict mold outbreaks or the risk of mechanical damage to the materials. The PEMdata features such as custom graphs and access to the National Oceanic and Atmospheric Administration (NOAA) outdoor data also make the site useful for storing and viewing data from industrial and commercial activities.

PEMdata is a free service of the Image Permanence Institute (IPI), a non-profit research laboratory devoted to preservation of images and information. IPI is a department of the College of Imaging Arts and Sciences of Rochester Institute of Technology (RIT) in Rochester, NY, USA.

Storing data on a web server has powerful advantages for ease of use and accessibility to data. You always know where your data is, and it is accessible to you to as well as anyone else you choose to share it with, at any time or place.

PEMdata was created to be the place where data from the PEM family of dataloggers can be viewed and analyzed. PEM® is short for ‘Preservation Environment Monitor,’ a battery-powered electronic device that measures temperature and humidity and stores the data for later upload into a computer. (Such a device is often referred to as a ‘datalogger.’)

The Image Permanence Institute, with funding from the National Endowment for the Humanities, designed the PEM datalogger in the late 1990s specifically for use in museums and libraries. In 2008, IPI introduced the second generation PEM, called the PEM2®, with many new features. The PEM2 is less expensive, smaller, and easier to use than the original PEM. The PEM2 data files are downloaded through a USB port as plain, ASCII text. No software is required to use and upload data from the PEM2, just a computer (Mac or PC) with web access. This is essential to the PEM2’s design because it facilitates storage and analysis of environmental data on the web, rather than the use of an application on a local computer.

PEMdata is a web site where temperature and humidity data can be stored, graphed, and analyzed in a very convenient way. Users first upload their data to the web site. The site stores the data on the server indefinitely. Once uploaded, users can manipulate their data in a number of ways to generate reports or extract information useful for the preservation of collections or HVAC management. Users can see graphs, overlay up to five datasets on one graph, set limits for Temperature (T) & Relative Humidity (RH), and calculate percentage of time within limits. In additon, they can print, save, or e-mail the graphs and analysis.

PEMdata supports data files from the PEM and the PEM2, as well as database files (.dbf) from IPI’s application software, Climate Notebook®.

Note: Within Climate Notebook, each data notebook is associated with three different files: a notebook file (.nbk), a database file (.dbf), and a configuration file (.cdx). ONLY the Climate Notebook data base files (.dbf) can be uploaded to PEMdata. The database files should be found with your .nbk files, wherever you are saving them on your local computer.

IPI recommends its PEM2 datalogger for this purpose. (The original PEM, though still supported by this website, is no longer available to purchase.) The PEM2 is a highly accurate temperature and humidity instrument that has a unique way to convey the data up to the PEMdata website. The PEM2 has a socket where any common USB flash drive can be inserted. In just a few seconds, the PEM2 copies its data to a text file on the USB drive. When the user is ready to upload the data to the web, the user can insert the USB drive into a computer with web access and log into the PEMdata site. From the upload page, browse to the file(s) on the USB drive and upload the data. No software is required to use and upload data from the PEM2, just a computer (Mac or PC) with web access. (Refer to the Upload Dataset page).

Yes. PEMdata incorporates graphs and statistics of IPI’s Preservation Metrics, a set of algorithms that process temperature and humidity data into numerical estimates of deterioration risks that threaten museum and library collections. The metrics relate to specific types of decay, characterizing the risk of mold growth, the rate of spontaneous chemical change in organic material (what might be called ‘natural aging rate’), and the mechanical risks posed by excessive dryness, dampness, and dimensional change in water-absorbing materials such as wood and paper.

Yes. Perhaps the most useful feature for HVAC management is the ability to compare outdoor conditions with indoor conditions. PEMdata incorporates an easy way to obtain outdoor Temperature (T) & Relative Humidity (RH) data from more than 1400 National Oceanic and Atmospheric Administration (NOAA) weather stations in the United States. HVAC engineers can choose outdoor data to overlay with their indoor data to determine how much heating, cooling, humidification, and dehumidification is occurring. Overlaying dew point curves is particularly helpful in diagnosing HVAC system performance.

PEMdata allows you to observe your data in many ways. You can overlay graphs of Temperature (T) and Relative Humidity (RH) or view individual graphs of Temperature (T), Relative Humidity (RH), and Dew Point. Because PEMdata includes calculations of IPI’s Preservation Metrics, you can also view graphs of the Mold Risk Factor (MRF), the Preservation Index (PI), the Time Weighted Preservation Index (TWPI), the Dimensional Change (% DC), and the Equilibration Moisture Content (% EMC).

PEMdata allows you to observe your data as numerical values, listing the minimum, maximum, mean, and median values for each type of data. If you choose to set upper and lower limits for Temperature (T) and Relative Humidity (RH), PEMdata will also calculate the percentage of time spent above, below, and within the target range for each dataset.

The following acronyms are used throughout the PEMdata site:

Acronyms	Definition
T	Temperature
RH	Relative Humidity
DP	Dew Point
PI	Preservation Index
TWPI	Time Weighted Preservation Index
DC	Dimensional Change
EMC	Equilibration Moisture Content
MRF	Mold Risk Factor

PEMdata is a free service. There are two ways to use the site, as registered or non-registered user. Registered users have access to all the features. Non-registered users cannot store data; they can upload and view one dataset at a time. To register, you must provide your email address and create a password. An email will be sent to you with the confirmation code necessary to complete your registration. Your email address will become your account login name, but if you prefer to use another login, you will be able to change your user name and password from within the Utilities page of your PEMdata account. (Refer to the Password section within the Utilities page).

PEMdata is housed on a physically secured server operated by GoDaddy, Inc. The server data is backed up daily. IPI makes no claims or guarantees to protect user’s data beyond reasonable care. Users should keep backup copies of the data they upload to protect themselves against accidental loss of server data. Users should not put sensitive or confidential information into the names of datasets on PEMdata. For most users, the kind of content that users are allowed to upload to PEMdata — names of datasets and the temperature and RH data itself — should not pose security issues for their organizations.

IPI will not sell or release e-mail addresses or any other information to any third party. IPI may periodically send registered users e-mails concerning PEMdata features and updates. Data and all content posted to PEMdata will be kept confidential. Users may post or remove data from PEMdata at any time.

Yes. Each account on PEMdata has a master login and master password. However, you can extend access to the account by creating additional passwords for use with the master login. The account owner can create or remove as many additional passwords as desired. (Refer to the Account section within the Utilities page).

Yes, but each account must have a different master login (username).

Each time you upload data into your PEMdata account, the website will prompt you to name your dataset. The name you assign will be associated with the serial number of that PEM2 (PEM1 or the filename of the DBF file) and will be saved in your account. Each time you upload data with that filename or serial number, the website will prompt you to confirm the location name. If you continue with the same name, the new data will be added to that dataset. If you change the name, a new dataset will be created and the serial number will have a new association.

If you would like to change the name of a dataset, go to the Dataset tab on the Utilities page. Select the dataset you would like rename from the drop down list and enter the new name in the text box below. The new dataset name will appear in your PEMdata account.

Renaming a dataset in the Utilities page will NOT disrupt the connection between the dataset and the associated PEM2 serial number. The website will recognize the dataset has been renamed the next time the data is uploaded.

When you name your dataset after uploading it to your PEMdata account, the website associates the given location name and the serial number of the PEM2. Each time you upload data from that PEM2, the website will recognize the name you previously assigned. The name will not appear, however, if you view your data outside of the website (i.e., as a text file or in Excel).

When you assign a name to your PEM2 with a command file created in the Configuration Utility, the name is saved in the log file of the PEM2. If you view your data as a text file, the location name will appear in the header. If you open your data in Excel, the location name will be imported with the data.