When seismographic measurements are required the following shall apply: A record of each blast shall be kept. All records including seismographic reports shall be retained at least 4 years and shall be available for inspection and shall contain the following minimum data: Name of blasting company or blasting contractor; Location, date, and time of blast; Name, signature, Social Security number of blasters; Type of material blasted; Number of holes, burden, and spacing; Diameter and depth of holes; Type of explosives used; Total amount of explosives used; Maximum amount of explosives per delay period of 8 milliseconds or greater; Maximum number of holes per delay period of 8 milliseconds or greater; Method of firing and type of circuit; Direction and distance in feet to nearest dwelling house, public building, school, church, commercial, or institutional building not owned or leased by the person conducting the blasting; Weather conditions (including such factors as wind direction and cloud cover); Height or length of stemming; Mats or other protection used; Type of detonators used and delay periods used; The exact location of the seismograph, and the distance of the seismograph from the blast; Seismographic readings; Name and signature of person operating seismograph; Name of person and the firm analyzing seismographic record. All field seismographs shall record the full analog wave form of the three mutually perpendicular components of motion in terms of particle velocity. All seismographs shall be capable of internal dynamic calibration and shall be calibrated according to the manufacturer's recommendations. Official Tables.