A University Products How-To Tip: Temperature & Humidity

Temperature and Humidity
Besides light, there are additional environmental concerns, such as temperature and humidity, that can  adversely affect a collection. For every 18 degree F (10 C) increase in temperature, it is estimated that chemical reactions in paper double. Relative humidity is a measure of the capacity of air to hold water. This amount varies as temperatures increase or decrease. Paper and other porous materials either absorb or lose moisture as temperature and humidity levels vary. This action causes shrinking, stretching, and the eventual breakdown of structural fibers, while contributing to formation of acids. The effect is similar to the cracking, splitting, and weaknesses that result when an outdoor wooden deck is left unprotected, though on a microscopic level.

While the ideal temperature and relative humidity levels for proper storage of paper are yet to be agreed upon, consistency seems to be the key factor. The best advice is to treat your collection like one of the family. Hot attics and damp basements make poor living quarters; they also make poor storage facilities. Even a closet that abuts an outside wall may be exposed to a large range of temperature and RH fluctuations over the course of a year.

Monitoring
Maxant HygrothermographWhen properly monitored, the combination of heating and air conditioning equipment, as well as humidifiers and dehumidifiers, allows the maintenance of a stable climate. There are also a variety of tools (with a variety of price levels and degrees of sophistication) that can assist in the monitoring. When fluctuations can be controlled, acid formation and mechanical degradation can be slowed significantly.

Desiccants
In the absence of expensive equipment, RH levels can be controlled and stabilized with the help of desiccants such as Silica Gel. Silica Gel is a porous granular, chemically inert amorphous silica that can absorb 40% to 50 % of its own weight in water. The material comes in several forms including reusable canisters, beads, sheets, and packets. Because it can become fully saturated, Silica Gel must be monitored and reconditioned when saturation occurs. One form of Silica Gel changes from orange to a pale pink to indicate it has reached the saturation level. Again, a proper schedule of monitoring your collection should be maintained to achieve a stable environment.

Having addressed the problems associated with fluctuations in temperature and humidity, it is equally important to address the more obvious problems which occur with constant extremes. The combination of high temperature and relative humidity promotes mold growth and encourages insect infestation, whereas a cold and dry environment leads to embrittlement. As you may have guessed, neither scenario is going to improve the condition of your collection.

Acceptable temperatures in your storage area should remain lower than 68 degrees F, with relative humidity between 30 and 50%.  Fluctuations should not exceed +/- 5 degrees F in temperature, and  +/- 3% relative humidity within a 24 hour period.

Most museums and libraries strive to achieve the ideal conditions described above, but they may fall under the same restraints that you and I are likely to come across. Lack of time, expertise, and money can prevent us from achieving ultimate conditions. In addition, each of our individual geographic locations can present problems unique to that area. All we can do is strive for improvement.

Resurrecting the Uniform and Memory of William Cannonball Jackman

Throughout the history of Baseball’s Negro Leagues during the early 20th century, virtually every player had a nickname, such as “Cool Papa” Bell, Bullet Joe Rogan, and Scrappy Brown. These colloquial names given to ballplayers by fellow ballplayers, added some flair to the league’s brand of baseball. The man nicknamed “Cannonball,” William Jackman, is perhaps one of the sport’s most talented, yet unknown legends. His nickname derived from his blistering fastball, and his career statistics showcase over 200 victories, nearly 800 strikeouts, and 48 shutouts during a 20-year career. His talents saw sportswriters compare Jackman, who was once dubbed “The Greatest Player You’ve Never Heard Of”, to big league Hall-of-Famers like Walter Johnson and Grover Cleveland Alexander. During his career, Major League Baseball was segregated and remained so until second baseman (and future Hall-of-Famer) Jackie Robinson broke in with the Brooklyn Dodgers on April 15, 1947. Some baseball historians believe that Jackman had the talent necessary to succeed in the big leagues, had the league integrated earlier. Jackman pitched into his mid-50s until retiring from baseball in 1953. He died in 1972 at the age of 74.

Uniform of Boston Royal Giants player William "Cannonball" Jackman after conservation. (Photo courtesy of Museum of African American History, Boston and Nantucket, MA.)

A uniform worn by Jackman in his playing days with the Boston Royal Giants, has been given a second life by our friends at Museum Textile Services in Andover, Massachusetts. Included in the entire uniform package is a jersey, pants, belt, cleats, socks, stirrups, two rosin bags, and some pads. The uniform is being preserved and stabilized by MTS in an effort to have it included in the Museum of African American History‘s “The Color of Baseball in Boston” exhibit opening on May 19. With any fabric item, insects are a concern. After the initial insect damage was attended to by placing the object in an anoxic fumigation chamber, these items were subsequently cleaned with a HEPA vacuum. Using Ethafoam, conservators carved out a head mold to be used as a display piece for Jackman’s hat. This mold will be used to display the piece during exhibition. Conservators also used a Preservation Pencil which relaxed the fabric and released old adhesives. This tool directs hot or cold water vapor from an ultrasonic humidifier.

University Products has an all-star lineup of products that can help you complete a similar project. We carry the proper conservation tools such as HEPA vacuums, Ethafoam planks and rolls, foam saws and knives, as well as preservation pencils to bring your prized memorabilia back to life. We also offer ready-made display products including  conservation suit forms and head mounts to help you showcase your collection.