Overview

For two decades, Sequoia Scientific, Inc. in Bellevue, WA, has been the world’s only manufacturer of portable, field, and submersible laser particle sizers.

The US Geological Survey approves our trademark LISST laser particle sizers for field use and they are a standard in other parts of the world (e.g. China).

LISSTs are used for environmental monitoring, industrial, and scientific applications across the globe: Our unique submersible LISSTs help engineers, scientists, and monitoring agencies reliably measure the concentration and size of sediment, plankton and oil droplets in any water body.

For a wide range of industrial applications, from hydropower turbine monitoring to optimization of drilling operations, our portable and industrial LISSTs will get the job done.

For optical studies (e.g. underwater visibility for defense purposes), our HydroLight software package and submersible VSF meters are indispensable.

Environmental

Environmental monitoring often requires real-time measurements of parameter in the field under often challenging conditions. Measuring particles in particular requires measurements that our done very close in time to the sampling of the water. As soon as the water is taken out of its original environment and placed into a sample bottle it is already beginning to change. Particles are settling to the bottom and possibly clumping together. When these samples are later processed they need to be mixed very hard or even ultrasonicated to bring the samples into solution to measure particle size and concentration. Now the particles are not the same as they were in the original environment. Sequoia developed instrument that are portable and field deployable that allow measurements to be made immediately after sampling (LISST-Portable|XR) or automatically on a regular schedule (LISST-StreamSide) by pumping water through the instrument. In addition we have developed automatically controlled three-way valves (FlowControl) that can be used to select multiple sources or filtered and unfiltered source water.

Energy

The LISST products are used for a wide range of applications in the Energy markets.  This includes real-time monitoring of sediments in Hydropower applications using the LISST-Infinite and LISST-Hydro and onsite analysis of drilling fluids using the LISST-Portable|XR.  The LISST-StreamSide is used for continuous monitoring on rivers and streams feeding reservoirs