such as small cracks (microcracks) within a material when stressed, typically in the 31 laboratory. AE is a similar phenomenon to microseismicity (MS), as MS is induced by 32 fracture of rock at an engineering scale (e.g. rockbursts in mines), that is, in the field. Thus, 33 seismic monitoring can be applied to a wide variety of rock engineering problems, and AE is 34 a powerful method to investigate processes of rock fracture by detecting microcracks prior 35 Manuscript ic r t n a Manuscript t c 2 to macroscopic failure and by tracking crack propagation. 36 A basic approach involves the use of a single channel of data acquisition, such as with a 37 digital oscilloscope, and analyzing the number and rate of AE events. Perhaps the most 38 valuable information from AE is the source location, which requires recording the waveform 39 at several sensors and determining arrival times at each. Thus, investing in a multichannel 40 data acquisition system provides the means to monitor dynamics of the fracturing process. The purpose of this suggested method is to describe the experimental setup and devices 42 used to monitor AE in laboratory testing of rock. The instrumentation includes the AE 43 sensor, pre-amplifier, frequency (noise) filter, main amplifier, AE rate counter, and A/D 44 (analog-to-digital) recorder, to provide fundamental knowledge on material and specimen 45 behavior in laboratory experiments. When considering in-situ seismic monitoring, the reader 46 is referred to the relevant ISRM Suggested Method specifically addressing that topic (Xiao 48 49 2. Brief Historical Review 50 2.1 Early Studies of AE Monitoring for Laboratory Testing 51 AE / MS monitoring of rock is generally credited to Obert and Duval (1945) in their seminal 52 work related to predicting rock failure in underground mines. Laboratory testing was later 53 used to understand better the failure process of rock (Mogi 1962a). For example, the nature 54 of crustal-scale earthquakes from observations of micro-scale fracture phenomena was a 55 popular topic. Mogi (1968) discussed the process of foreshocks, main shocks, and 56 aftershocks from AE activity monitored through failure of rock specimens. Scholz (1968b, 57 1968c) studied the fracturing process of rock and discussed the relation between 58 microcracking and inelastic deformation. Nishizawa et al. (1984) examined focal 59 mechanisms of microseismicity, and Kusunose and Nishizawa (1986) discussed the concept 60 of the seismic gap from AE data obtained in their laboratory experiments. Spetzler et al. 61 (1991) discussed stick slip events in pre-fractured rock with various surface roughness by 62 combining acoustic emission with holographic intereferometry measurements. Compiling 63 years of study, Scholz (2002) and Mogi (2006) published books on rock failure processes 64 from a geophysics perspective. Hardy (1994, 2003) focused on geoengineering applications 65 of AE, while Grosse and Ohtsu (2008) edited topics on the use of AE as a health monitoring 66 method for civil engineering structu...