Saw this install at a project in a newly built warehouse. The blue colored pull station is there to release the standpipe solenoid. The standpipe is dry, not holding water, because it is installed in a huge freezer where if the piping held water it would freeze. The intent of the manual Pull station is to fill or release the mechanism holding back the water. NFPA 72 allows a manual Pull station for other than alarm initiation as long as the pull station is of a different color other than red.
220.127.116.11 Manual pull stations for initiating other than fire alarm shall be permitted if the devices are differentiated from the manual fire alarm boxes by a color other than red and labeling.
Looking for our NICET Fire Alarm System Exam Study Guides?