3. Close case. Rotate selector switch to zero position (figure 2). Allow instrument to warm up for about 2 minutes.

4. Rotate zero know until pointer is on zero of the meter scale (figure 2).

5. Rotate selector switch counter clockwise to circuit check position and hold. Meter should give an up-scale reading in or near red area marked "Circuit Check." If not, replace battery and repeat above steps until a better battery is found. Then
you will be eady to measure the radiation rate. If after trying several batteries and performing steps 3 through 5 the meter fails to give an up-scale reading in or near the read area marked "Circuit Check", the instrument is faulty and should NOT be used.

6. Rotate selector switch clockwise to X100, X10, X1 or XO.1 switch position. Use swich position that produces highest on-scale meter reading.

7. Multiply meter reading by final switch setting to obtain exposure rate. EXAMPLE: Reading in figure 3 is 2.5 (meter reading). times switch setting (which is times 100) for an exposure rate of 250 Roentgens per hour (R/hr).

8. Survey (move instrument about) shelter to locate area giving lowest reading. This is the preferred area.

9. Improve this part of the shelter by placing furniture, books and other materials between area of lowest reading and areas of higher readings.


A dosimeter is used to measure your body's accumulated exposure to radiation. It measures the total amount of radiation your body is exposed to in a manner similar to the way an odometer in a vehicle measures the total miles traveled. It is used together with the survey meter to determine and verify the value of your shelter. A pocket clip is provided so that it may be fastened to a person's clothes.