Environmental Monitoring Equipment & Supplies • Sales, Rental & Service by Enviro-Equipment — Charlotte, North Carolina USA

The Tape

The specially coated measuring tape connects the probe with the housing assembly and provides an accurate means of measuring the distance from the well head or tank port to the air/water, air/oil or oil/water interface. The tape also contains all the wiring running between the probe and the circuitry in the housing assembly.

The Probe

The probe is a 1" (25mm) in diameter cylinder which can be used in wells as small as 1-1/8" (29mm) in diameter. The probe contains two different sensor units, one for detecting the liquid/air interface, and one for for distinguishing between water and hydrocarbon. The liquid sensor is an optical prism located on the end of the probe. This sensor detects liquid by reacting to the differences in the indices of refraction of air and liquids. An infrared light source is internally reflected to an unfired detector by a prism on the face of the sensor.

The Housing

The housing includes a casing and reel to protect and deploy the measuring tape and probe. The housing also has a Low Battery indicator, a visual/audible alarm and a test button for the alarm. A grounding clip is attached to the housing.

Title Daily Rate Weekly Rate Monthly Rate
ORS 100 FT Interface Probe Rental $50.00 $150.00 $425.00

The ORS Interface Probe™ is a hand held, battery powered device for measuring depth to water or oil in tanks or wells. The ORS Interface Probe™ can be used in numerous applications including measuring oil and water levels in monitoring wells, and obtaining accurate measurements of water levels in cascading wells. The system is Factory Mutual Approved for Class 1, Division 1, Group D applications.

When the prism becomes immersed in liquid, the light beam is refracted away from the detector. To determine if the liquid is conductive (water) or nonconductive (hydrocarbon), a small Intrinsically Safe electrical cable is passed between two electrodes on the sensor. Current flow will occur only in conductive fluids such as water. The Interface probe is capable of measuring oil slicks less than 1/16 of an inch (1.6mm) in thickness.

Items Included:
  • ORS Interface Probe (100 ft)
  • Hard Carrying Case
  • Instruction Manual
  • Spare Battery



304 Stainlees Steel, Radel


4.6 oz / 130 grams


1 inch / 25 mm


6 1/2" / 165 mm


100 psi / 6.9 bar

Maximum Probe Shock

10 G

Conductivity sense range

> .78 IS

Minimum detectable hydrocarbon thickness

0.0312" / < .8 mm



Kynar Coated Stainless Steel

Length / Weight

100' (30m) / 7.7 lbs (3.5 kg) with case 15.2 lbs (6.9 kg)


100th of a foot per 100 ft, per Federal Specification GGG-T-106E



100'/30m 13" H x 12" W x 3 ¼" D
330mm H x 300mm W x 80mm D
w/Case 20" H x 14" W x 8" D
510mm H x 360mm W x 205mm


9 VDC (Six, Duracell Type MN1500 size AA)

Self shut off time

4 minutes

Output tone (hydrocarbons)

500 Hz typ

Output modulation tone (water)

3.5 Hz typ


Operating temperature

32°F / 0°C to 140°F / 60°C

Storage temperature

-40° to 170°F / 75°C


5-95% non-condensing

ORS Interface Probe User Manual257.56 KB