A number of stages of laboratory testing had been done before field testing. Landfill surface simulator was designed and commissioned to test the sampling adaptor. The simulator underwent several stages of improvement, that had been discused at project team meatings. These improvements lead to development of simulator, that allowes to test sampling adaptor at given known fluxes of methan through the simulator surface. The dependence between measured values of average methane concentration measured by the sampling adaptor (ppm methane) and the methane flux liters * m-2 * hour, produced by the simulator, has been tabled and curve of dependence plotted. These experiments are still in progress due to delays caused by complexities of achievement steady flux of methane through the simulator, but there is an indication of close to linear dependence of methane concentration measured by the sampling adaptor and methane flux through the landfill surface simulator.