Rhapid Gel is a new form of silica gel, developed by APS, for the passive control of relative humidity in museum exhibition and storage cases. Due to its exceptional moisture buffering characteristics in the mid RH range (40-60%) and extremely rapid rate of response, it is much more efficient than any other silica gel product for museum applications.

Rhapid Gel consists of tiny silica gel beads embedded within a 3 mm (1/8th inch) thick porous polyester sheet, containing 0.11 pounds of silica gel per 1 ft�. One sheet (18" x 18") will condition approximately 1-1.5 cubic feet of case volume. One 18" x 18" sheet (0.45m x 0.45m) contains approximately 0.25 lb silica gel (113g). These recommendations are based on average exhibition conditions using standard assumptions about leakage rates and RH conditions within and outside the exhibit case. See Silica Gel FAQs for calculating amounts of silica gel.

The sheet can be cut easily with a utility knife or scissors to any size or length. Since it is both sturdy and flexible, there are many options for how it can be located in an exhibit case or storage container, either horizontally or vertically. The material has an enormous surface area ratio, resulting in the fastest response time to changes in relative humidity among all high performance silica gels. For large case volumes, gel sheets can be stacked on top of one another without an air gap and without any loss in efficiency within the depth of the stack. The rapid response time gives users the capacity to re-utilize and re-condition the gel as needed. When placed in a container at the target relative humidity, it will fully equilibrate in two days time. Alternatively, the silica gel sheet can be re-conditioned within the exhibition case. To increase relative humidity, place a damp wicking pad (such as those sold for residential evaporative humidifiers) in the case. To dehumidify, add dry gel to the case (please refer to our pdf. file on Reconditioning Silica Gel). Due to the polyester matrix, it is not recommended that people attempt to lower the humidity of the gel sheet by heating the material in an oven or microwave.

Art Preservation Services introduces Scavengel for the passive control of gaseous pollutants in museum exhibition and storage cases. Due to its unique composition and design, it is very effective in removing a broad range of common indoor pollutants over a very short period of time. Due to its high load factor, it also has a very high capacity for removing gaseous pollutants. Scavengel consists of small grains of two types of pollution scavengers embedded within a 2 mm (1/16 inch) thick porous polyester sheet, containing 500g of media per square meter of material (0.1 pound per square foot).

• activated alumina impregnated with 8% potassium permanganate
• activated carbon granular media

In part, the effectiveness of Scavengel is based on the combination of two types of media. Potassium permanganate, a strong oxidizing chemical, breaks down pollutants whereas activated carbon adsorbs pollutants within its enormous network of internal capillaries. The combination of a chemisorption and physical adsorption process is the key to the material's broad-spectrum capacity to remove a very wide range of pollutants.

The effectiveness of Scavengel is further improved by the rate at which it adsorbs pollutants in a passive application. Because each small grain of media floats within Scavengel's porous polyester matrix, there is an enormous surface area available, permitting a rapid response between the material and the pollutant.

Please continue to check on our website - www.apsnyc.com - for the most current information on our new pollution removal media and best methods of application.