This paper presents a series of measurements documenting changes in electrical and optical properties of thin palladium films. Palladium is deposited on the glass surface through plasma-assisted physical vapor deposition. This process produces highly uniform films with a surface variation of a few nanometers. The thicknesses of studied films range from 15 to 60 nm. The films are exposed to a constant flow of 2% hydrogen and 98% nitrogen mixture. During the exposure, film resistivity and its reflection properties in visible light were monitored. It is observed that the change in the film resistance during the hydrogen exposure depends on the film thickness. In particular, thicker depositions exhibit larger relative changes of the resistance. The reflectivity of the films in the white light changes during the hydrogen exposure as well. However, the change of the film reflectivity is observed to be independent of the deposition thickness. This paper presents observed measurements, their quantitative analysis and briefly discusses the use of findings in development of low-cost, single-use commercial grade hydrogen sensors.