4 BURRIDGE RADON INSTRUMENTATION RAD7 RADON DETECTOR User Manual Owner Serial SERVICE RECORD Date Service It is recommended that the unit be returned to DURRIDGE Company annually for recalibration DURRIDGE Company Inc 524 Boston Rd Billerica MA 01821 Tel 978 667 9556 Fax 978 667 9557 service durridge com Revision 7 4 0 2015 DURRIDGE Company www durridge com WARNING Opening the cover of this instrument is likely to e
PURRIDGE RADON INSTRUMENTATION Natural Rock Sample Manual NATURAL ROCK SAMPLE Granite gravel 1 3 Ib 0 6 kg Serial No RS DURRIDGE Company Inc 524 Boston Road Billerica MA 01821 Tel 978 667 9556 Fax 978 667 9557 service durridge com www durridge com Revision 2014 06 12 2014 DURRIDGE Company Inc Table of Contents Introduction Fig 1 Natural Rock Sample Components 1 RAD7 Radon Sensitivity Check