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#11
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#12
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Perhaps they moved the detector or found a way to block the building to allow the chemical fog into the building itself. The laser detection system is based on blocking the beam itself since micro-particles show up the same, whether real smoke or chemical-based. Most home-based smoke detectors operate on the same system. Another possible solution is to install heat-detectors so breaking the beam isn't the basis for setting the system off. Or it could simply be, as Jeremy mentioned, that it was a rare occurance that the wind blew the fog back into the facade, thus they could simply shut off the fog machine.
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"Six Flags is what you wish the world could be!"
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#13
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There's 2 types of smoke detectors, the photoelectric type and ionization type, which style is used at SFOT? I dont think anyone here knows.
Ionization Detectors Ionization detectors have an ionization chamber and a source of ionizing radiation. The source of ionizing radiation is a minute quantity of americium-241 (perhaps 1/5000th of a gram), which is a source of alpha particles (helium nuclei). The ionization chamber consists of two plates separated by about a centimeter. The battery applies a voltage to the plates, charging one plate positive and the other plate negative. Alpha particles constantly released by the americium knock electrons off of the atoms in the air, ionizing the oxygen and nitrogen atoms in the chamber. The positively-charged oxygen and nitrogen atoms are attracted to the negative plate and the electrons are attracted to the positive plate, generating a small, continuous electric current. When smoke enters the ionization chamber, the smoke particles attach to the ions and neutralize them, so they do not reach the plate. The drop in current between the plates triggers the alarm. Photoelectric Detectors In one type of photoelectric device, smoke can block a light beam. In this case, the reduction in light reaching a photocell sets off the alarm. In the most common type of photoelectric unit, however, light is scattered by smoke particles onto a photocell, initiating an alarm. In this type of detector there is a T-shaped chamber with a light-emitting diode (LED) that shoots a beam of light across the horizontal bar of the T. A photocell, positioned at the bottom of the vertical base of the T, generates a current when it is exposed to light. Under smoke-free conditions, the light beam crosses the top of the T in an uninterrupted straight line, not striking the photocell positioned at a right angle below the beam. When smoke is present, the light is scattered by smoke particles, and some of the light is directed down the vertical part of the T to strike the photocell. When sufficient light hits the cell, the current triggers the alarm. Which Method is Better? Both ionization and photoelectric detectors are effective smoke sensors. Both types of smoke detectors must pass the same test to be certified as UL smoke detectors. Ionization detectors respond more quickly to flaming fires with smaller combustion particles; photoelectric detectors respond more quickly to smoldering fires. In either type of detector, steam or high humidity can lead to condensation on the circuit board and sensor, causing the alarm to sound. Ionization detectors are less expensive than photoelectric detectors, but some users purposely disable them because they are more likely to sound an alarm from normal cooking due to their sensitivity to minute smoke particles. However, ionization detectors have a degree of built-in security not inherent to photoelectric detectors. When the battery starts to fail in an ionization detector, the ion current falls and the alarm sounds, warning that it is time to change the battery before the detector becomes ineffective. Back-up batteries may be used for photoelectric detectors. |
#14
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We didn't use smoke detectors on side 4 this year. We just had Merv keep an eye out.
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81-82 Colonel's Cafe, 2008 HR - Temp, 2009 Rapids & Superman, 2014 Texas Giant, Boot Scootin' & Steam Train PIC, 2015 Steam Train. 2016-2017 Side 4 Supervisor, Steam Train. Head Trainer. Co-creator of the soon to be Johnson Creek Station Museum. 2018 back at the Railroad for my 9th season! |
#15
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of course mine always seem to fail in the middle of the night, and there is nothing more annoying than that beep a detector makes, and of course it's always the one you have o have the ladder/step stool for
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#16
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Ah yes, but you can't use a ladder until you have been certified -- to not fall off.
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__________________
81-82 Colonel's Cafe, 2008 HR - Temp, 2009 Rapids & Superman, 2014 Texas Giant, Boot Scootin' & Steam Train PIC, 2015 Steam Train. 2016-2017 Side 4 Supervisor, Steam Train. Head Trainer. Co-creator of the soon to be Johnson Creek Station Museum. 2018 back at the Railroad for my 9th season! |
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