The Aperture Science Material Emancipation Grid, also known as Portal Fizzler or simply Fizzler, is a testing element featured right before any elevator at the end of each Aperture Science Enrichment CenterTest Chamber, within some Test Chambers where they are part of the test, in administrative areas, and at the entrance of GLaDOS's chamber.
The purpose of this "incandescent particle field" is mostly to "reboot" any portal created with the ASHPD. In that way each Test Subject starts each new Test Chamber with a "clean" portal network, and must use their assets properly when having to come across one several times during tests. The Material Emancipation Grid's design is a similar, albeit sleeker form of the Combine's Force Field, but in a semi-reverse fashion: It allows authorized personel through, but not inanimate objects. The sides are two curved emitters with a pair of blue stripes on each, which disperse waves of glowing particles, slowly moving from one side to the other. The Material Emancipation Grid vaporizes any unauthorized equipment (Weighted Storage Cubes or any other prop or NPC) that passes through it. When this happens, the object (besides the ASHPD) turns black, slowly hovers in mid-air, then disintegrates in some sort of silent fire emitting sparks, just like objects hit with the alternate fire of an OSIPR. GLaDOS states that it "emancipates" dental fillings, crowns, tooth enamel, and teeth, but only in "semi-rare cases". She also states that a noticeable taste of blood may occur, although it is an unintended side effect. The Rocket Sentry's rockets also vaporize while going through the Material Emancipation Grid, but will, before disappearing, turn on themselves at a high speed instead of slowly hovering. When clipboards disappear, they do not emit any fire or spark and vanish upon contact with the first wall. Some objects such as the squared metal panels found in the maintenance area before the first Rocket Sentry are not affected by the Emancipation Grid (this is likely a developer's oversight, since the player has no reason to take these panels in the following offices). Each time Chell passes through a Material Emancipation Grid, the ASHPD will slightly shake and the light on its body will turn off until fired again, showing the portal "reboot". When being put through a Material Emancipation Grid, a Sentry Gun will emit a long "ayayayayay" and vaporize, whether it is disabled or not. When a radio is brought through the Material Emancipation Grid, its music stops as the radio disintegrates. Since the March 2010 updates made to Portal as part of the ARG, the radio makes three other sounds ("dinosaur_fizzle.wav", "dinosaur_fizzle2.wav" and "dinosaur_fizzle3.wav") when disintegrating. Any NPC (such as a Headcrab, Alyx, Combine Soldiers, etc.) will also be vaporized by the Material Emancipation Grid. This may partially explain how GLaDOS keeps the Aperture Science Center free of both Combine and Alien infestation as both are vaporized on contact. The Material Emancipation Grid is sometimes referred to as "Material Emancipation Grill" both in audio files and subtitles. The term "Grid" is used instead in the wiki as it is the term used in scripts and the Portal Prima Guide. According to Garret Rickey, the combination of the Material Emancipation Grids and the elevators serve a dual purpose. They provide a clearly identifiable end-point for each Test Chamber, while also addressing the more practical problem of how to keep players from portaling across level loads, eventually leading to the integration of Material Emancipation Grids in the tests themselves.