The Gigacarbi GR Filter is a heavy duty gas-phase filtration solution built around the proven performance of loose granular activated carbon and chemically impregnated media for removing odours and corrosive gases from recirculation units, supply air, and extract air systems. The loose-fill granular construction maximises the contact surface area between the airstream and the adsorptive media, enabling contaminant gases to be removed by both adsorption and chemisorption — the two complementary mechanisms by which molecular contaminants are permanently bound to the media rather than simply displaced. The availability of activated carbon, chemically impregnated carbon, activated alumina, and blended carbon-alumina media impregnated with KMnO₄ allows the media specification to be precisely matched to the target gas or gas mixture, covering odorous compounds including SO₂, H₂S, NO₂, formaldehyde, ammonia, amines, and aldehydes. For complex or multi-contaminant applications, multiple stages of gas phase filters can be employed to achieve the required removal efficiency. Perforated metal or plastic mesh support on both sides of the tray retains the granular media securely under all operating airflow conditions, while the optional neoprene gasket seals the tray against the housing frame to prevent bypass. The refillable tray design is a significant operational advantage — spent granules can be returned to the factory for replacement, restoring full filter capacity without the need to replace the metal frame structure, reducing both cost and waste over the filter’s service life. Factors to be considered in media selection include available space, airflow volumes, residence time, contaminant type and concentration, and desired media life — all of which inform the correct tray depth, media type, and number of filter stages for the application.