Of fog fluid is from Lightjockey mist generated for most short-term show effects, or to highlight the light beams.
Fog fluids for common fog machines mainly consist of distilled water and propylene glycol . There are also systems in which anhydrous oils are used. Composition and chemicals used vary and are usually not specified by the manufacturer. Some fluids come with a TÜV certificate. Moderate warming without burning the components of the fluid creates a mist. Consumption in discos is on the order of a few liters per night.
The longer the "standing time" in the air, the higher the concentration of stabilizing additives. Also Glycerin is one of the substances that increase the service life of the nebula. If this is burned by excessively high temperatures beyond nebulization, this can lead to the formation of the very toxic and carcinogenic acrolein . A reliable temperature control of the fog machines by sufficient and thus cooling liquid flow or in an electronic way is important.
In addition to the aforementioned show effects, the fog also makes air currents visible and can thus also check the effectiveness of ventilation and fume cupboards. Gas leaks can be found by placing the mist in closed systems or on suspected exit points of a pressurized system, where it swirls visibly in the positive case. In sewer systems, all exit and entry points are visible through fog flooding. In this way, illegal discharges can usually be detected without entering private property. For example, a gutter in a separation system could be connected to the sewage system instead of the rainwater system. Reverse exchanges would also be possible. In buildings, the prescribed roof ventilation of the waste water pipe can also be checked. In all cases, the human perception of the fog can be enhanced by focusing light as possible on the incident site and low ambient brightness.
Before today's fog fluid was used since the 1970s, significantly more complex dry ice was added to heated water to generate fog . Contrary to the newer fluid, the mist generated in this way left strong moisture at the place of use, e.g. B. on dance floors and was so less suitable. Effect fog can also be created by relaxing and evaporating liquid carbon dioxide . For this purpose, pressurized gas cylinders with a riser pipe are used and a piece of pipe with a large lumen connected to the expansion nozzle. Part of the CO 2 emerges as "carbonic acid snow"; its sublimation cools the ambient air, from which water vapor condenses as a mist.
In 1973 Günther Schaidt, who lives in Schenefeld near Hamburg, developed today's fog fluid and machines for it. In these, a mixture of double-distilled water (to prevent mineral residues) and high-purity glycols is pressed, for example with a piston pump, through a check valve into a tubular heating element heated to approx. 300 ° C with a narrow scale and evaporated. The glycol vapor then condenses when it exits the nozzle of the device and at the same time the jet breaks down into "visible mist" in the form of microscopic droplets (aerosol). Schaidt received a technology Oscar for this development in Hollywood .
Common abbreviations are:
FF Fast Fog Fluid with a normal density and an extremely short service life (CO 2 effect).
B Standard fluid with a normal density and medium-long service life.
C Standard fluid with a normal density and a long service life.
P Professional fluid with high density and long service life.
E Extreme fluid with high density, very long service life.
DSA special fluid with high density and short service life.
X Extreme fluid with extreme density and extremely long service life.
- Jürgen Meier: Fog fluids - Presentation and assessment of the most varied of ingredients in fog fluids
- What does which fluid do? - Fog fluid under the microscope. Steinigke Showtechnic (PDF)