The invention relates to flame-guard filters (F) consisting of a number of layer sequences (S1, S2, S3), wherein each of the layer sequences (S1, S2, S3) consists of filter layers (1, 2) arranged on top of each other. Each layer sequence (S1, S2, S3) consists of a first filter layer (1) and of a second filter layer (2), each made of a material arranged in a lattice formation and having openings (1.1, 2.1), each with an opening width (1.11, 2.11). The first filter layer (1) having a free side face (6.3) is a first end-filter layer (3) with a first end- filter opening width (3.11), and the second filter layer (2) having a free side face (6.4) is a second end-filter layer (4) with a second end-filter opening width (4.11). The second opening width (2.11) of a second filter layer (2) is smaller than the first opening width (1.11) of a first filter layer (1). The second filter layer (2) is opaque. The invention further relates to an arrangement (10) of at least two flame-guard filters (F1, F2), and also to a housing (9) which is encapsulated in a pressure-resistant manner and has at least one flame-guard filter (F, F1, F2).