Safe Operation of the Electron Microscope

Revision 0 (8/2003)

    1. This procedure provides instructions for safe operation of Electron Microscope.
    1. Sign in.
    2. Fill cylinder with LIQUID NITROGEN.
    3. Green "evacuation" light should be on.
    4. PULL "column" switch up and then PUSH to on.
    5. Depress black "H.V." button (at the left) - red light should go on and red needle (at left) should go up to 75.
    6. Numbers for magnification should light up.
    7. Turn "Filament" knob (at left) up slowly until you see the green beam in the scope. Use "Brightness" knob (left side) to focus beam to a small spot.
    8. Beam initially should have a dark area in the middle of the spot. Turn up "Filament" knob until dark area just disappears - then turn DOWN a small amount. Red needle (at left) should be between 90 and 100.
    9. Center beam with "Brightness Centering" knobs x and y (at right).
    10. Use "Brightness" knob (at left) to spread beam to fill field of view and adjust brightness as desired.
    11. Turn filament down before putting in specimen. Turn off high voltage (H.V.) button.
    12. Pull out specimen holder - don't touch brass.
    13. Pull back tab with wooden stick.
    14. Remove brass cap with forceps.
    15. Put grid in recess with specimen side DOWN.
    16. Replace brass cap. Be sure tapered edge goes back under the holder in proper position.
    17. Slide tab back into place - be sure tab is level with the brass cap.
    18. Put specimen holder back in scope with peg up and wait until you hear a second click; turn clockwise 180 to stop - holder will be pulled in somewhat by the vacuum (go in to the stop); turn again a small amount - holder should go in fully.
    19. Turn H.V. button on and bring filament up with "Filament" knob (see 2.8 & 2.9 above).
    20. Search for specimen - select magnification (knob and buttons at left), adjust focus (knobs at right), and adjust brightness (knob at left) as you go up or down in magnification.
    21. For critical focus use binocular scope - focus on + on small screen - obtain critical focus with focus knobs (at right).
    22. Take pictures - see directions.
    23. Go backwards through steps to shut down the scope:
      1. put on low magnification
      2. turn down filament
      3. turn off H.V.
      4. pull out specimen holder & remove grid
      5. put specimen holder back to first position
      6. turn off column switch (PULL UP then switch)
    1. Perform a wipe test of each of the areas shown on the diagram of VLCS, Room 1146. Also, if 32P or 33P is being utilized in radiological experiments, survey each of these areas using the survey meter.
    2. Record the activity level for each area on the form found in the white record keeping notebook in VLCS, Room 1146.
    3. Removable activity greater than 100 dpm/100 cm2 is considered contamination and must be decontaminated as follows:
      1. Clean the affected area(s) (using water or rad-con)
      2. Resurvey the area by wipe test.
      3. Record decontamination efforts and results of post-decontamination wipe tests on the survey form.