4336 Glass Bayard-Alpert

The ETI 4336 Series of ionization gauges are Bayard-Alpert gauges available either with a burnout-resistant iridium-coated filament or two tungsten filaments. ETI was the first to incorporate a bifilar design grid in its Bayard-Alpert gauges. Through this design, only one-half of the grid weight is suspended on each support, thereby making it more “sag resistant” during frequent outgassing conditions.



Tubulation3/4”, 1” Pyrex® or Nonex® glass or 3/4”, 1” Kovar® flanges are available
EnvelopeNonex® 7720 glass
Mounting PositionVertical
Collector.005” tungsten
FilamentThoria-coated iridium or tungsten
GridTungsten helix configuration


Sensitivity for N210/Torr
X-ray Limit2 × 10-10 Torr
Operating Pressure2 × 10-10 to 1 × 10-3 Torr
Electron-Bombardment Degas70 W
Resistance-Heated Degas6.3 V to 7.5 V @ 10 A
Bakeout Temperature250 °C

Pyrex® is a registered trademark of Corning.
Nonex® is a registered trademark of Corning.
Kovar® is a registered trademark of Westinghouse Electric Corp.