GE Hydran 201i Instruction Manual page 80

CAUTION
3. Do not touch the H201 sensor's membrane (located inside the threaded extremity)
with a finger or an object (see Figure 6-2 below). The membrane is easily
damaged; this would impair the sensor permanently, thus voiding the warranty.
4. Do not block or puncture the sensor's breathing membrane. Located above the
sensor's connector (see Figure 3-1) this opening provides oxygen to the gas
detector inside the sensor. Blocking or puncturing this membrane damages the
sensor permanently, thus voiding the warranty.
Page 80
Mishandling of the Hydran 201 sensor (such as a perforation or
scratch on the membrane or subjecting the sensor to paint or
solvent) voids the warranty.
Figure 6-2: Do Not Touch the Membrane
Hydran* 201i Instruction Manual
MA-033 Rev. 14.0, 12-Nov-18