A differential pressure recorder in a completely self-contained package, designed from the beginning to be extremely flexible yet easy to use. The included accessories, owner's manual, hose, a spare roll of paper and AC cord, store easily in the lid. Accurate measurements continue even if the unit is moved. Pressure is indicated with large easy to read characters and alarm setpoints are always displayed. Screen icons show the monitoring, printer and audible alarm status with a glance. Pressure readings are time stamped and logged into memory once containment has been established. Audible and visual alarms activate whenever the pressure reaches the alarm setpoints. The Omniguard 4 ensures the site inspector that proper containment was maintained. Logs and summary reports can be printed at any time for easy inspection of the monitoring data.