In the Friuli Venezia-Giulia region, the margins of burnt forest areas are surveyed with GPS by the personnel of the Central Direction of agricultural, natural and forestry resources of the Regional Authority. A method to assess the positional accuracy of linear features, is applied here to the surveys of the margins of four burnt areas used as test sites. The method estimates the percentage of the total length of the tested survey that falls within a buffer created around the reference survey, which is more accurate.