Electromagnetic waves are generated by acoustic waves at interfaces between fluids and fluid-saturated porous media, and at porous medium interfaces between different fluids. These signals can be measured in the laboratory as predicted by theory. A potential application is oil spill remediation monotoring in soils. We designed and developed an experimental setup in which acoustic to electromagnetic (EM) wave conversions at interfaces can be measured. Theoretical results are obtained with an electrokinetic full-waveform theoretical model, where use was made of the Sommerfeld approach. Using bimodal samples, different fluid–solid interface effects and saturating fluids were investigated. The contrast between water and water-saturated porous glass samples is larger than the contrast between water and oil-saturated porous glass samples. The contrast between water and water-saturated Fontainebleau sandstone is larger than the contrast between oil and water-saturated Fontainebleau sandstone.