Abstract: A ratchet mechanism for a hard hat and method of assembling the same are provided. The ratchet mechanism includes a knob with knob protrusions. The ratchet mechanism also includes a ratchet gear. The ratchet gear includes teeth engagement mechanisms. Each teeth engagement mechanism includes a hooking mechanism and a tooth protrusion. Each hooking mechanism is configured to engage with the knob protrusions. The ratchet mechanism also includes a band housing configured to allow a band to ratchetably move within the housing. The band housing also includes a knob engagement protrusion and a ratchet gear aperture configured with one or more teeth defining a ramped surface. The ratchet gear is disposed on the knob engagement protrusion and includes one or more ratchet gear teeth configured to engage with a set of band teeth on the band, such that the rotation of the ratchet gear tightens or loosens the band during operation.

Abstract: A ratchet mechanism for a hard hat and method of assembling the same are provided. The ratchet mechanism includes a knob with knob protrusions. The ratchet mechanism also includes a ratchet gear. The ratchet gear includes teeth engagement mechanisms. Each teeth engagement mechanism includes a hooking mechanism and a tooth protrusion. Each hooking mechanism is configured to engage with the knob protrusions. The ratchet mechanism also includes a band housing configured to allow a band to ratchetably move within the housing. The band housing also includes a knob engagement protrusion and a ratchet gear aperture configured with one or more teeth defining a ramped surface. The ratchet gear is disposed on the knob engagement protrusion and includes one or more ratchet gear teeth configured to engage with a set of band teeth on the band, such that the rotation of the ratchet gear tightens or loosens the band during operation.

Abstract: A ratchet mechanism for a hard hat and method of assembling the same are provided. The ratchet mechanism includes a knob with knob protrusions. The ratchet mechanism also includes a ratchet gear. The ratchet gear includes teeth engagement mechanisms. Each teeth engagement mechanism includes a hooking mechanism and a tooth protrusion. Each hooking mechanism is configured to engage with the knob protrusions. The ratchet mechanism also includes a band housing configured to allow a band to ratchetably move within the housing. The band housing also includes a knob engagement protrusion and a ratchet gear aperture configured with one or more teeth defining a ramped surface. The ratchet gear is disposed on the knob engagement protrusion and includes one or more ratchet gear teeth configured to engage with a set of band teeth on the band, such that the rotation of the ratchet gear tightens or loosens the band during operation.

Abstract: Embodiments relate generally to a connector for a powered air-purifying respirator (“PAPR”). A powered air purifying respirator (PAPR) connector may comprise a tab extending from the PAPR connector, wherein the tab is positioned to contact an inner surface of a housing; and a flange extending from the PAPR connector, wherein the flange is configured to receive an attachment mechanism, wherein the attachment mechanism is configured to attach the PAPR connector to the housing; wherein the PAPR connector is rotatable within the housing.

Abstract: Embodiments relate generally to a connector for a powered air-purifying respirator (“PAPR”). A powered air purifying respirator (PAPR) connector may comprise a tab extending from the PAPR connector, wherein the tab is positioned to contact an inner surface of a housing; and a flange extending from the PAPR connector, wherein the flange is configured to receive an attachment mechanism, wherein the attachment mechanism is configured to attach the PAPR connector to the housing; wherein the PAPR connector is rotatable within the housing.

Abstract: A low pressure warning device that comprises a piston located inside the device, where the piston partitions the device into a first chamber communicating with a first opening and a second chamber communicating with a second opening, an adjustable stop, and a spring located inside the device and configured to bias the piston to a position based on a position of the adjustable stop and based on a pressure differential between the first opening and the second opening, wherein a low pressure differential warning state is associated with a position of the piston.

Abstract: A low pressure warning device that comprises a piston located inside the device, where the piston partitions the device into a first chamber communicating with a first opening and a second chamber communicating with a second opening, an adjustable stop, and a spring located inside the device and configured to bias the piston to a position based on a position of the adjustable stop and based on a pressure differential between the first opening and the second opening, wherein a low pressure differential warning state is associated with a position of the piston.