The co-ed air raid wardens and the special Navy ARP platoons, as wen as the faculty and student members of the civilian defense organization at Harvard functioned efficiently in yesterday's test air raid.

When the horn stop Widener went off about 4 o'clock, the Navy was drilling in the Yard, and many people were standing around watching them. Several classes were in session in Sever and the other Halls. But within a very few minutes of the siren's wall, the Yard was cleared, passers-by and students were sent to shelter, and the Yard ARP force was in good working order.

Two changes have been made in the procedure for wardens, it was announced last night. From now on, in all such tests, wardens must stay on duty for twenty minutes after the all-clear signal, which is one long, continous blast, has sounded.