Abstract: A powered room air purifier with a visual indicator of air quality, the visual indicator including: a reflector that defines a forwardly-open-ended reflecting cavity and that includes at least one through-opening in a floor or ceiling of the reflector; at least one diffuser layer that covers the forward opening of the forward-open-ended reflecting cavity; and, at least one LED light source that is positioned within the at least one through-opening, the LED light source and the reflector being configured so that the LED light source is shielded from line-of-sight view along a forward-rearward axis of the powered room air purifier.

Abstract: Wall anchors and assemblies of the present disclosure include a plate, one more prongs, and a load bearing structure comprising a threaded bolt, post, or threaded bore. The prongs are typically integral with a side edge of the plate and are typically curved towards the bottom edge of the plate.

Abstract: A room air purifier including upper and lower portions with the lower portion including a detachable floor panel. The upper portion and the floor panel may respectively include integrated resilient upper and lower gaskets configured so that with an air filter removably installed in the room air purifier and with the floor panel attached to a lower housing piece of the lower portion of the room air purifier, the upper portion of the room air purifier, and the floor panel, apply pressure to the air filter through the upper and lower gaskets.

Abstract: A room air purifier including upper and lower portions. The upper and lower portions may include integrated resilient upper and lower gaskets configured so that with an air filter removably installed in the room air purifier and with the upper and lower portions attached to each other, the upper and lower portions apply pressure to the air filter through the upper and lower gaskets.

Abstract: A room air purifier including first and second portions. The first portion includes a locking ring and the second portion includes a mandrel configured to receive an unframed air filter. The locking ring can be secured to the mandrel to join the first and second portions to each other to form the room air purifier.

Abstract: A powered room air purifier with a visual indicator of air quality, the visual indicator including: a reflector that defines a forwardly-open-ended reflecting cavity and that comprises at least one through-opening in a floor or ceiling of the reflector; at least one diffuser layer that covers the forward opening of the forward-open-ended reflecting cavity; and, at least one LED light source that is positioned within the at least one through-opening, the LED light source and the reflector being configured so that the LED light source is shielded from line-of-sight view along a forward-rearward axis of the powered room air purifier.

Abstract: A powered room air purifier including a non-movable air filter holder. The room air purifier may include at least one guide ramp located at an upper end of the air filter holder. An air filter may be installed into the air filter holder by a combination of translational and rotational movement of the air filter.

Abstract: The present disclosure describes devices for detecting fine and ultrafine particulate matter. The devices may include at least one optical sensor configured at an angle of greater than 90 degrees from a direction of air flow, such that particulate matter is carried away from the sensor. In some examples, a device includes a housing, a light source and a light trap. The light source may be disposed within the proximal end of the housing and can be configured to direct a beam of light toward the distal end of the housing. The light trap may be disposed within the housing to reduce backscatter from the beam of light.

Abstract: The present disclosure provides adjustable mounting devices that allow the user to fine tune the placement of a mountable item without concern about the precise placement of the mounting device. Certain mounting devices may be used to hang pictures, and may be rotated once mounted on a vertical surface.