A gas sampling apparatus for extraction of a gaseous sample from a gaseous environment comprising flue gas comprising solid particles, wherein the gas sampling apparatus comprises - a housing having a housing wall enclosing an interior of the housing, wherein the housing wall comprises an exterior housing surface, an interior housing surface, a rim surface connecting the exterior housing surface and the interior housing surface and enclosing a housing opening directed towards the gaseous environment during use, the housing opening is positioned in an open end of the housing, wherein the open end of the housing is arranged to be positioned inside the gaseous environment, during use, and wherein the housing opening is configured to provide fluid communication between the gaseous environment and the interior of the housing, - a sample system for extracting the gaseous sample, wherein the sample system comprises at least one sample pipe having a first opening, wherein at least the first opening is enclosed by the housing wall and is configured to be in fluid communication with the gaseous environment, and filter means comprising at least one filter for filtering a plurality of solid particles from the gaseous sample, wherein the filter is enclosed by the housing wall and arranged at the first opening of the sample pipe and in the open end of the housing, wherein the gas sampling apparatus further comprises - a central purge system configured to remove aggregates of solid particles deposited on one or more housing surfaces (3a, 5, 6) by means of a gaseous medium, such as air, wherein the central purge system comprises at least one first inner and center-most purge pipe comprising an first outlet opening directed towards the housing opening and enclosed by the housing wall, wherein the sample system is arranged externally to the central purge system so that at least the sample pipe(s) are separate to the first inner and center-most purge pipe(s), and characterized in that the filter, such as the entire longitudinal extent of the filter, is arranged radially between an exterior surface of the first inner and center-most purge pipe and the housing. - a housing having a housing wall enclosing an interior of the housing, wherein the housing wall comprises an exterior housing surface, an interior housing surface, a rim surface connecting the exterior housing surface and the interior housing surface and enclosing a housing opening directed towards the gaseous environment during use, the housing opening is positioned in an open end of the housing, wherein the open end of the housing is arranged to be positioned inside the gaseous environment, during use, and wherein the housing opening is configured to provide fluid communication between the gaseous environment and the interior of the housing, - a sample system for extracting the gaseous sample, wherein the sample system comprises at least one sample pipe having a first opening, wherein at least the first opening is enclosed by the housing wall and is configured to be in fluid communication with the gaseous environment, and filter means comprising at least one filter for filtering a plurality of solid particles from the gaseous sample, wherein the filter is enclosed by the housing wall and arranged at the first opening of the sample pipe and in the open end of the housing, wherein the gas sampling apparatus further comprises at least one sample pipe having a first opening, wherein at least the first opening is enclosed by the housing wall and is configured to be in fluid communication with the gaseous environment, and filter means comprising at least one filter for filtering a plurality of solid particles from the gaseous sample, wherein the filter is enclosed by the housing wall and arranged at the first opening of the sample pipe and in the open end of the housing, wherein the gas sampling apparatus further comprises - a central purge system configured to remove aggregates of solid particles deposited on one or more housing surfaces (3a, 5, 6) by means of a gaseous medium, such as air, wherein the central purge system comprises at least one first inner and center-most purge pipe comprising an first outlet opening directed towards the housing opening and enclosed by the housing wall, wherein the sample system is arranged externally to the central purge system so that at least the sample pipe(s) are separate to the first inner and center-most purge pipe(s), and characterized in that the filter, such as the entire longitudinal extent of the filter, is arranged radially between an exterior surface of the first inner and center-most purge pipe and the housing.