Section 154.1850 - Entering cargo handling spaces(a) The master shall ensure that the ventilation system under § 154.1200 is in operation for 30 minutes before a person enters one of the following: (1) Spaces containing cargo pumps, compressors, and compressor motors.(2) Gas-dangerous cargo control spaces.(3) Other spaces containing cargo handling equipment.(b) The master shall ensure that a warning sign listing the requirement for use of the ventilation system, is posted outside of each space under paragraph (a) of this section.(c) The master shall ensure that no sources of ignition are put in a cargo handling space on a vessel carrying flammable cargo unless the space is gas free.