UI definition

Requirements

'84.312 Low Pressure indicator; minimum requirements
(a) For positive pressure PAPR, a low pressure indicator must actively and readily indicate
when pressure inside the respiratory inlet covering falls to ambient pressure
(b) Low pressure indicators must be readily visible or detectable (via sound or vibration) to the
user without manipulation of the respirator
'84.313 Low flow indicators; minimum requirements
(a) For non-positive pressure PAPR, a low flow indicator must actively and readily indicate if
the airflow inside the respiratory inlet covering drops to the minimum specified flow rate in this subpart.
(b) Low flow indicators must be readily visible or detectable (via sound or vibration) to the user
without manipulation of the respirator
'84.314 Full and low battery power indicator, minimum requirements
(a) Each PAPR equipped with a battery must contain an indicator to show when the battery is
fully charged
(b) Each PAPR equipped with a battery must contain a low battery indicator and must indicate
when or before when the battery can no longer provide the unit with 15 minutes of additional adequate
power to properly power the unit at the lowest recommended operating temperature and at the highest
flow demand with the highest resistance combination of cartridges/canisters/filters
(c) Low battery indicators must be readily visible or detectable (via sound or vibration) to the
user without manipulation of the respirator