By order of the Swiss Civil Defence Authority shelter doors have been tested at the RSFA 1) experimental station at Märsta under the supervision of the author. Totally eight doors were tested subjected to shock wave overpressure. Six of the doors were intended for 800 x 1850 mm openings and the other two for 600 x 800 mm openings. The structural behaviour of the bigger doors was found to be satisfactory as regards nominal loads. However, reconsiderations concerning the locking of the handles and the design of the rubber strip around the doors are suggested from the results of the tests. The smaller doors - which opened towards the interior of shelters - were deformed at the handles as much as to violate their function. Stiffer handles are suggested together with a good fitting of them at manufacturing. Improvements of the locking of the handles and of the installation of the rubber strip are suggested as well. The tests are nonconservative with respect to leakage pressure. The leakage pressures registered for the bigger doors indicate, however, that the leakage pressure from a nominal load will not be jeopardizeing for practical purposes.