gimbel wrote:Let’s start with the basics.
Humidification beads are a moisture sensitive silica material which absorbs and desorbs moisture in order to offset changes in relative humidity (RH) in your humidor. The beads are generally available preset to a specific RH, in the case of cigars 60%, 65% and 70%. Opinions differ as to what is the “best” RH for cigars but most BOTLs seem to prefer 65% and that is my experience as well.
Humidification beads were first developed for the art and museum industry and are used extensively by that industry for the stable storage of priceless artifacts and art. The manufacturer I purchase the beads I sell also supplies places such as the Smithsonian and The National Archives.
A question that is often asked; “Are humidification beads the same as ordinary desiccant silica gel?” Definitely NOT! Humidification beads give off water vapor, as well as absorb it, to maintain a specific RH which is ideal for a cigars particular need. This is not the case with silica gel which can only absorb water then must be dried out after it is saturated. By nature silica gel is not meant to control humidity, only lower it. Humidification beads are the premier product for precise control in terms of performance, cost effectiveness, and simplicity.
A lot of that is pure marketing speak and is largely just flat wrong and with no basis in science. Silica gel beads come in several varieties with the main three being nano-pore (type A), micro-pore (type B) and wide (or macro) pore (type C). Each type has specific characteristics which lend them to be suited for particular uses.
Type A nano-pore beads are generally best suited to desiccant-only use. Type-A beads have a very narrow range of humidity response regardless of temp (within limits) or humidity (within limits) up to their capacity to absorb moisture. Since the appearance of the various types of silica gel beads is pretty much identical, an easy way to ID type A beads is to spray or soak them with water. Type A nano-pore beads will fracture (break into many pieces/turn to sand) in the presence of liquid water.
Type B and Type C are both suitable for humidity control and the level of humidity (the set point) is based on pre-conditioning and the essentially linear response curve of these bead types. Type B and Type C beads tend to adsorb (not absorb) moisture at high relative humidity levels and desorb as humidity levels fall. This response curve is why Type B and Type C beads are in fact the base products for humidity control in contained museum exhibit and gallery use. (Artsorb.) (See some response curves for the various types of silica gels in the charts at Broadchem* at http://www.broadchemical.com/FAQs/index.htm and WR Grace at http://www.grace.com/engineeredmaterials/MaterialSciences/SilicaGel/SilicaGelTypes/SilicaGelTypeAdsorption.aspx.) Beads are not "pre-set" as "pre-set" implies that beads will maintain one specific level of humidity up to the limits of adsorption (saturation) or desorbtion (dry.) Silica gel beads are instead "pre-conditioned" (which is to say they are "set" to a level of RH at a certain temperature by exposing them to the desired RH at the desired temp until they achieve equilibrium.)
Heartfelt beads are just plain silica gel type B or Type C beads. Nothing more. Nothing less. There is nothing magic about them except the price. Buy the cheapest Type B or Type C beads you can find and use those. The silica beads in some brands of cat litter** are suitable. (It isn't cat litter until your cat uses it. It's just silica gel.)
Sorry if I've stepped on any toes here, but this is an area I happen to know something about based on years of work for the archives at the Air War College at Maxwell AFB in Montgomery, AL. I had wondered about Heartfelt and their claims for a while. I have no idea if they believe what they are saying or if they just don't understand the science. Either way, their product is nothing special. Just over priced.
*The Broadchem charts are probably the more instructive. Suffice to say that these charts show that both Type B and Type C beads have the ability to adsorb more moisture at high levels of RH and less moisture at low levels of RH. Think about what that means and you will see that contra the marketing speak claim ("
Humidification beads give off water vapor, as well as absorb it, to maintain a specific RH which is ideal for a cigars particular need. This is not the case with silica gel which can only absorb water then must be dried out after it is saturated"), Type B and Type C beads do in fact have the inherent ability to both adsorb and desorb. In fact, even Type A beads can both adsorb and desorb moisture, but the limited response curve of such nano-pore beads is not well suited for RH set-point stabilization so much as for drying.
**Crystal Clear Litter Pearls are generally Type B, Type C or some mixture of the two and are perfectly suited for the purpose of cigar humidor humidity stabilization and control.
