Siemens RAPIDLAB 248, Operator'S Manual, Page: 107 / 135

Appendix B Precautions and Hazards
Operating Precautions
• The 248 is designed to be left connected to an a.c. supply. To
prevent damage to the instrument do not leave it switched off
unless the shutdown procedure (Section 3) has been followed.
• Never turn the pump rotors anticlockwise. If a bubble is detected
samples should be moved forwards until there are no air bubbles
beneath the sensors.
• Use Siemens Healthcare Diagnostics collection devices as the
heparin coating has been specially formulated.
• Use only Siemens approved QC materials.
• Only Siemens reagents and supplies should be used with the 248
(with the possible exception of gas/regulator, Page 3-10).
Do not use reagents after the expiry date shown on the label.
Do not use 7.382 and 6.838 buffer for longer than 30 days once
opened. Do not decant solutions from one bottle to another as this
can cause contamination. Agitate the Buffer Pack daily, to
incorporate any solution that may have condensed on to the inside
surface of the bottles. It is advisable to empty the waste bottle daily
and add approximately 10 mL of disinfectant or sodium
hypochlorite to the bottle. When replacing the Buffer Pack or Wash
bottle always remove the waste bottle and put the empty 7.3 Buffer
or Wash bottle in its place. Siemens recommends that
approximately 10 mL of disinfectant or sodium hypochlorite is put
into the empty bottle before placing it in position as the new waste
bottle.
• When sampling from syringes position the probe to obtain the most
representative sample - do not allow probe tip to touch the syringe
plunger. Obstructing the probe tip can cause sampling faults, and,
in extreme cases, calibration instability.
If you suspect the probe tip was obstructed during sampling, we
recommend cancelling the sample analysis, and calibrating the 248,
Page 2-9.
• Do not release the measurement block catch unless the instrument
has been stopped using the
STOP SYSTEM routine.
• Make sure that routine maintenance is carried out at the intervals
stated in Section 3.
• Make sure the drip tray is always in place and is correctly
connected.
• The maximum non-destructive voltage that can be applied to the
data ports is
±
12V d.c. to pins 3 and 8 (data receive and clear to
send connections), Page D-1.
Page B-1