Chest seal

A chest seal, comprising:

• a release layer (1);
• an adhesive layer (2), wherein a center of the adhesive layer (2) is opened with an exhaust through hole (21);
• a backing layer (3), wherein the adhesive layer (2) is arranged between the release layer (1) and the backing layer (3);
• the backing layer (3) comprises a lower backing layer (31) and a soft backing layer (32);
• the lower backing layer (31) and the soft backing layer (32) overlap at their respective inner peripheral regions (313, 323) to form an elongated overlapping area (33);
• the lower backing layer (31) is arranged above the adhesive layer (2) and partially blocks one side of the exhaust through hole (21), a non-block area (22) is formed at another side of the exhaust through hole (21) between the lower backing layer (31) and the exhaust through hole (21), and the soft backing layer (32) completely covers the non-block area (22);
• the elongated overlapping area (33) comprises two connection areas (331) disposed at two opposite ends of the elongated overlapping area (33) respectively, and a non-connection area (332) disposed between the two connection areas (331);
• wherein the non-connection area (332) is located above the exhaust through hole (21) and defines a flow path (333) between the inner peripheral regions (313, 323) of the lower backing layer (31) and the soft backing layer (32);
• and the soft backing layer (32) is configured to close the flow path (333) to prevent inward airflow and permit outward flow of effusion from the non-block area (22) through the flow path (333);
• the lower backing layer (31) comprises an inner periphery (311) and an outer periphery (312);
• the inner periphery (311) is provided with at least one notch (3111);
• the notch (3111) is arranged in the elongated overlapping area (33);
• and the notch (3111) is in fluid communication with the exhaust through hole (21).