Respondent was assessed a civil penalty of $4,360 for two violations of the HMR when it represented, marked, and certified DOT specification and special permit compressed gas cylinders as having been successfully retested and qualified for continued service in accordance with the HMR, on days when it failed to assure that its retest equipment was accurate to within ±1.0% at test pressures within 500 psi of the pressures at which it retested cylinders (violation No. 1), and failed to maintain complete and accurate records of calibration and cylinder requalification (violation No. 2).