Deep Sampling DIS Operating Principles

To overcome buoyancy, weights are connected to the top of the Deep Sampling Discrete Interval Sampler before lowering. After the first 100 m (300 ft), one 2 kg weight is added for every additional 100 m (300 ft) of submerged depth.

Once the sampler reaches the desired sampling depth, it is pressurized. Using the basic principles of hydraulics, the pressure acts on the top of a piston (larger surface area) inside the sampler, overcoming the hydrostatic pressure acting on the bottom of the piston (smaller surface area) to allow sample water to enter.

As sample water fills the sampler, air from the sampler is vented through holes (covered with a Vyon filter) on the side of the sampler, which are also opened with the applied pressure.

After the sample is collected, the pressure is released, allowing the piston to reseal at the bottom of the sampler. The sealed sampler is then retrieved to surface, maintaining chemical stability of the sample.

At surface, the sample is collected by reapplying pressure to the Discrete Interval Sampler. The flow of the sample is regulated by the amount of pressure applied. The sampler is easily disassembled for decontamination.


Recommended Operating Pressure and Weights
Submerged Depth (feet) Pressure (psi) Submerged Depth (meters) Pressure (kPa) Number of Weights
160 50 50 345 0
320 50 100 345 0
640 50 200 345 1
960 75 300 520 2
1280 100 400 690 3
1600 125 500 860 4
1920 150 600 1030 5
2250 175 700 1200 6
3250 200 1000 1380 9
The 1.66" ø x 2' (42 mm x 610 mm) Deep Sampling DIS has a capacity of 420 ml (14 oz).
Sampling at deeper depths may be possible, contact Solinst to determine the suitability of your application.



425 d deep discrete interval sampler operating principles illustration