If the Dräger Pac 8000 measures hazardous gas concentrations, it sets off an audible, visual and noticeable vibrating alarm. Two bright, ﬂashing LEDs on the top and bottom of the device ensure that the alarm is easily visible from all sides. The acoustic signal reaches a volume of 90 dBa. The display can show the peak concentration measured at any given moment. Earlier alarms registered can also be retrieved at a later time, even if acknowledged. The single-gas detector for ammonia (NH3) is protected against water, dust and other foreign bodies by a special membrane ﬁlter. When the ﬁlter becomes heavily soiled in use, it can be quickly replaced. The sensor warranty is 2 years. It measures from 0 to 100 ppm with a 1 ppm resolution.