(225 ILCS 710/45.50) (from Ch. 96 1/2, par. 4303)

Sec. 45.50. The safety catches of cages shall be kept well oiled and in good working order, and shall be tested at least once a month. Such test shall consist of releasing the cage suddenly in some suitable manner so that the safety catches shall have an opportunity to grip the guides.

(Source: Laws 1945, p. 1035.)