2.3.3 Mercury Manometer (Used for Calibration)
The mercury manometer is calibrated when it is manufactured and, once calibrated, re-calibration is unnecessary. However, regular inspection is necessary to eliminate conditions that could
cause the blood pressure measurement to be read as erroneously high or low.
Check to see that the level of mercury in the glass tube is zero. The level of the
mercury in the calibrated glass tube should always be at the zero line when the
manometer is on a level surface with the inflation system disconnected. Tip the
manometer gently to the right and then to the erect position. If the top of the mercury
column does not return to zero, replace the equipment. Check the shape of the meniscus - it should be a smooth, well-defined curve. Check that the mercury rises easily in the tubing and that the mercury column does not
bounce noticeably when the valve is closed. Check for cracks in the glass tube to make sure it is securely in place. Check cap at top of the calibrated glass tube to make sure it is securely in place. Check cuff, pressure bulb, and manometer for cracks or tears. Check pressure control valve for sticks or leaks. Use the following procedure to check for air leaks:- Put the male luer plug in the female luer adapter on the Y-connector.
- Connect the male connector on the manometer to the female connector on the
Y-connector. - Inflate to 250 mm Hg.
- Open valve and deflate to 200 mmHg and close valve.
- Wait for 10 seconds. If mercury column falls more than 10 mm Hg, there is an
air leak in the system.
Never attempt to repair the equipment yourself. Contact the MEC manager to have equipment sent for repair or replacement. The
manometer will be sent to the home office and from there will be sent to Baum for
repair or replacement.