A platform ladder apparatus having a transport position and a use position in which the apparatus is arranged to lean against a wall for performing work at an elevated level, said apparatus comprising: a ladder having a front side for climbing and a rear side facing the wall in the use position; a working platform having, seen from the front side of the ladder, a right side, a left side, a proximal side and an opposite distal side, the proximal side of the platform being pivotally connected to the ladder at a platform pivot axis located at an upper end of the ladder, the platform being arranged, in the use position of the apparatus, to extend essentially horizontally out from the ladder with its distal side directed towards the wall, and the platform being arranged, in the transport position of the apparatus, to be pivoted about the platform pivot axis towards the ladder to a stowed position essentially parallel to the ladder; and a foldable user safety railing which in the transport position of the apparatus is folded into a stowed position, and which in the use position of the apparatus is unfolded and arranged above the working platform for forming a protection for a user standing upon the platform, characterized in that said safety railing comprising: - right and left proximal posts arranged at the proximal side of the platform, - right and left distal posts arranged further towards the distal side of the platform; and - right and left guard rails which, in the use position of the apparatus, extends from the right and left distal posts, respectively, towards the wall, wherein the right guard rail extends between an upper end of the right distal post and an upper end of the right proximal post, and wherein the left guard rail extends between an upper end of the left distal post and an upper end of the left proximal post; wherein a distal end of the right and left guard rails, in the use position of the apparatus, are located at a distance (a) from the wall, and wherein said distance (a) is reduced to zero if and as a result of a lower end of the ladder should accidently slide on the ground away from the wall, whereby the left and right guard rails will counteract further sliding by frictional forces in relation to the wall. a ladder having a front side for climbing and a rear side facing the wall in the use position; a working platform having, seen from the front side of the ladder, a right side, a left side, a proximal side and an opposite distal side, the proximal side of the platform being pivotally connected to the ladder at a platform pivot axis located at an upper end of the ladder, the platform being arranged, in the use position of the apparatus, to extend essentially horizontally out from the ladder with its distal side directed towards the wall, and the platform being arranged, in the transport position of the apparatus, to be pivoted about the platform pivot axis towards the ladder to a stowed position essentially parallel to the ladder; and a foldable user safety railing which in the transport position of the apparatus is folded into a stowed position, and which in the use position of the apparatus is unfolded and arranged above the working platform for forming a protection for a user standing upon the platform, characterized in that said safety railing comprising: - right and left proximal posts arranged at the proximal side of the platform, - right and left distal posts arranged further towards the distal side of the platform; and - right and left guard rails which, in the use position of the apparatus, extends from the right and left distal posts, respectively, towards the wall, wherein the right guard rail extends between an upper end of the right distal post and an upper end of the right proximal post, and wherein the left guard rail extends between an upper end of the left distal post and an upper end of the left proximal post; - right and left proximal posts arranged at the proximal side of the platform, - right and left distal posts arranged further towards the distal side of the platform; and - right and left guard rails which, in the use position of the apparatus, extends from the right and left distal posts, respectively, towards the wall, wherein the right guard rail extends between an upper end of the right distal post and an upper end of the right proximal post, and wherein the left guard rail extends between an upper end of the left distal post and an upper end of the left proximal post; wherein a distal end of the right and left guard rails, in the use position of the apparatus, are located at a distance (a) from the wall, and wherein said distance (a) is reduced to zero if and as a result of a lower end of the ladder should accidently slide on the ground away from the wall, whereby the left and right guard rails will counteract further sliding by frictional forces in relation to the wall.