A head simulator, for testing respirators, has a head simulator body (2) with a simulated oral aperture (6) and with a simulated oral cavity (4), which is located behind the simulated oral aperture (6) in the head simulator body. A loudspeaker (8) is arranged in the simulated oral cavity (4). An audio unit (20) is connected to the loudspeaker (8) for reproducing speech via the loudspeaker (8). The head simulator includes a simulated trachea (10), which is in connection with the simulated oral cavity (4) and opens into the simulated oral aperture (6). An air delivery device (30) is provided, which can be operated to allow air to flow through the simulated trachea (10) and the simulated oral aperture (6).

A system and method for automated respirator fit testing by comparing three-dimensional (3D) images are disclosed. An example embodiment is configured to: obtain at least one three-dimensional facial image of an individual at an initial visit (Visit X); capture at least one current 3D facial image of the individual at a subsequent visit (Visit X+n); convert the Visit X image and the Visit X+n image to numerical data for computation and analysis; identify reference points in the Visit X data and the Visit X+n data; determine if the Visit X data and the Visit X+n data is sufficiently aligned; determine if any differences between the VISIT X data and the VISIT X+n data are greater than a pre-defined set of Allowable Deltas (ADs); and record a pass status if the differences between the VISIT X data and the VISIT X+n data are not greater than the pre-defined ADs.

A system and method for automated respirator fit testing by comparing three-dimensional (3D) images are disclosed. An example embodiment is configured to: obtain at least one three-dimensional facial image of an individual at an initial visit (Visit X); capture at least one current 3D facial image of the individual at a subsequent visit (Visit X+n); convert the Visit X image and the Visit X+n image to numerical data for computation and analysis; identify reference points in the Visit X data and the Visit X+n data; determine if the Visit X data and the Visit X+n data is sufficiently aligned; determine if any differences between the VISIT X data and the VISIT X+n data are greater than a pre-defined set of Allowable Deltas (ADs); and record a pass status if the differences between the VISIT X data and the VISIT X+n data are not greater than the pre-defined ADs.

The present disclosure provides a respiratory protection device that includes a valve assembly operable between an open configuration and a closed configuration. In some exemplary embodiments, the respiratory protection device includes an elastomeric seal, and a valve assembly and a breathing air source component are in sealing engagement with the elastomeric seal when the valve assembly is in the closed configuration.

In some examples, a system (1900) includes a hearing protector (1920); at least one position sensor; at least one sound monitoring sensor; at least one computing device configured to: receive, from the at least one sound monitoring sensor and over a time duration, indications of sound levels to which a worker is exposed; determine, from the at least one position sensor and during the time duration, that the hearing protector is not positioned at one or more ears of the worker to attenuate the sound levels; and generate, in response to the determination that at least one of the sound levels satisfies an exposure threshold during the time duration and the hearing protector is not positioned at one or more ears of the worker to attenuate the sound levels, an indication for output.

There is provided a fit testing method comprising: providing a respirator donned by a wearer; providing a sensor in electrical communication with a sensing element, where the sensor is configured to monitor a particulate concentration parameter of a gas space within the respirator, and a second particulate concentration parameter of a gas space outside the respirator, where the sensor is attached to the respirator such that the respirator such that the weight of the sensor is supported by the respirator; and providing a reader configured to communicate with the sensor, where the reader is configured to provide a respirator fit parameter based on a comparison of the particulate concentration within the respirator to the particulate concentration parameter outside the respirator.

There is provided a fit testing method comprising: providing a respirator donned by a wearer; providing a sensor in electrical communication with a sensing element, where the sensor is configured to monitor a particulate concentration parameter of a gas space within the respirator, and a second particulate concentration parameter of a gas space outside the respirator, where the sensor is attached to the respirator such that the respirator such that the weight of the sensor is supported by the respirator; and providing a reader configured to communicate with the sensor, where the reader is configured to provide a respirator fit parameter based on a comparison of the particulate concentration within the respirator to the particulate concentration parameter outside the respirator.

A rebreather apparatus includes at least one pressurized container of oxygen, at least one pressurized container of a diluting gas, and at least one valve to supply the oxygen and diluting gas to a rebreathing loop. The valve is controlled by a signal from at least one oxygen sensor, wherein the oxygen and diluting gas combine to form a breathing gas that is circulated by the rebreathing loop. At least one container of calibrating gas stores the calibrating gas at ambient pressure and temperature. At least one valve is connected to the at least one oxygen sensor presenting the calibrating gas to the oxygen sensor during calibration of the oxygen sensor and presenting the breathing gas to the oxygen sensor at all other times.

A rebreather apparatus includes at least one pressurized container of oxygen, at least one pressurized container of a diluting gas, and at least one valve to supply the oxygen and diluting gas to a rebreathing loop. The valve is controlled by a signal from at least one oxygen sensor, wherein the oxygen and diluting gas combine to form a breathing gas that is circulated by the rebreathing loop. At least one container of calibrating gas stores the calibrating gas at ambient pressure and temperature. At least one valve is connected to the at least one oxygen sensor presenting the calibrating gas to the oxygen sensor during calibration of the oxygen sensor and presenting the breathing gas to the oxygen sensor at all other times.

A packaged filtration mask comprising a filtration mask packaged in a container in a vacuum or a partial vacuum, wherein the packaged filtration mask comprises an indicator configured to indicate the presence of a vacuum or a partial vacuum in the container, or configured to indicate the lack of a vacuum or a partial vacuum in the container.