Seismograph 14 : An instrument, useful in monitoring blasting operations, that records ground vibration. Particle velocity, displacement, or acceleration is generally measured and recorded in three mutually perpendicular directions
United States Mine Rescue Association USMRA (membership,mine rescue and safety training resources, and mine disasters and accidents), Mine Safety and Health Quizzes, Glossary of Blasting Terms, PA,USA 2016. http: //miningquiz.com/pdf/Glossaries/Glossary_of_Blasti ng_Terms.pdf, (Blasting - Amer) {997}