Working With Gerb Effects
Often called a "spark fountain," a gerb effect produces a jet of sparks that can shoot anywhere from six to twenty feet into the air and last up to twenty seconds or more. The fallout from most gerbs is cold, which means that they can safely be used near actors and scenery. This property has made gerbs a very popular effect for rock bands who often mount them above the front of the stage to create a "waterfall" of sparks. Gerbs are also hugely popular with professional wrestlers, who use them to make their entrances to the ring more dramatic. This week, I'd like to look at how to use gerbs to create a great-looking, safe effect for your next production.
When selecting a gerb, there are three variables that you will have to address: height, duration and color. The product descriptions for all of our gerbs will specify how tall the effect is, how long it lasts and, if applicable, what color choices are available. To choose the appropriate height for your effect, consider the space in which it will be used. If you're in a club or restaurant with eight-foot ceilings, you'll want to stick with one of the smaller effects, while the larger fountains could be used at an outdoor show, or in a large theater.
If you'll be using the gerb in very close proximity to a performer or audience member (in a tabletop centerpiece, for example) you should probably consider using an Ice Fountain. The Ice Fountain produces a spark fountain that is much smaller than a typical gerb -- around 12 - 18 inches -- and burns at a much cooler temperature. While we advise against the practice, some performers have been known to hold an Ice Fountain in their hand while it burns, and we've no knowledge of any unusual problems resulting from such use.
When deciding on the duration of the effect, consider both how you want the effect to look and when in the show it takes place. If you are using your gerb indoors, in the beginning or middle of your event, you'll want to use the shortest duration you can get away with. This reason for this is simple: the longer a gerb burns, the more smoke it creates, and your audience doesn't want to sit in a room full of smoke. If you really want to use that 20 second gerb, use it at the end of the show so that the audience can quickly get out of the smoke.
Depending upon the type of gerb that you choose, you may or may not have a choice of colors. As a rule, all gerbs by all manufacturers are available in silver, but other colors may be available for specific gerbs. For example, the ProStage II gerb by LeMaitre is only available in silver, while the Ice Fountain can be had in silver, red, green or gold. The color you choose is really just a matter of personal taste as the color of the gerb doesn't noticeably change its performance. But if you simply must have a gerb in gold (or red, or green) be aware that it will limit your selection.
Even though gerbs are one of the safer pyrotechnics, it never hurts to use some common sense when setting up your effects. First, you should never place any pyrotechnic so that it's right next to or pointed directly at a piece of scenery, as this can cause scorching or, in extreme cases, start a fire. Allow at least a foot or two of clear space around the gerb and make sure that the spray won't hit any nearby curtains or scenery. You'll also want to provide a clear line-of-sight from the operator to the effect. The operator makes the final call on whether or not it's safe to fire the effect, so make sure your effects operator is someone whose judgment you trust!
Theatre Effects Customer Service Department
Theatre Effects, 1810 Airport Exchange Blvd. #400, Erlanger, KY 41018
Phone: 1-800-791-7646 or 513-772-7646 Fax: 513-772-3579