Remove all combustible materials, flammable or explosive, from the area where welding or cutting is to be done. When welding or cutting a bulkhead, deck, floor, or other structure, you should check both sides of the structure to ensure that no materials near the structure will be damaged or will become a possible fire hazard. Post fire watches on both sides of a deck or bulkhead before welding or cutting operations can be started.  Personnel  assigned  fire  watches  should  be thoroughly familiar with fire watch responsibilities and outfitted with the proper safety gear, such as gloves, proper eye protection (particularly when arc welding), and safety shoes. To make sure no fire hazards exist, personnel assigned to the duties of a fire watch must remain at the location at least 30 minutes after the job is completed. Keep  approved  fire-extinguishing  equipment near welding and cutting operations. Usually, a CO2 extinguisher is adequate. If the space is small or if the access  is  only  a  small  opening,  CO2    is  not  the extinguishing agent to use. CO2   could fill the small space,  and  the  small  opening  would  not  allow  for breathable air to enter. The small entry or exit may also hinder any rescue attempts should you be overcome by suffocation. If CO2   is not recommended, the use of water spray from a fog nozzle is preferred. In the event the fire is caused by electricity, secure power before using the water spray. Welding or cutting operations aren’t permitted in or on the outer surfaces of a compartment or tank that contains or has contained a flammable or explosive substance,  unless  applicable  safety  precautions  are observed. ROTATING MACHINERY The safe operation of rotating machinery and tools requires the operator to be thoroughly knowledgeable in the  equipment  operation.  It  also  requires  strict adherence  to  established  operating  procedures.  The operators should be familiar with the safety precautions for  their  own  particular  machinery.  However,  when operating  rotating  machinery,  the  following  general safety precautions should be observed: Never place any part of your body into moving machinery. Never attempt to ride machinery that is not designed for human conveyance. Never  wear  jewelry,  neckties,  or  loose-fitting clothing. Wear proper protective clothing and equipment suited  to  the  operation  being  performed  (hearing protection; eye, hand, and foot protection; dust and paint respirators; and so on). Before  attempting  to  perform  repairs  or preventive maintenance on any equipment, ensure that it is de-energized and/or depressurized and properly tagged out of service before beginning to work. When  working  in  the  vicinity  of  electrical equipment or electrical cables, be alert to the presence of  dangerous  voltages  and  avoid  striking  such equipment with tools of any kind. Should such damage inadvertently occur, report it immediately to the ship’s electrical officer. Don’t use compressed air to clean parts of your body or clothing or to perform general space cleanup. Compressed air may be used to clean machinery parts that have been properly disassembled provided that the supply air pressure does not exceed 30 psi and a safety shield tip is used. Reinstall  shaft  guards,  coupling  guards,  deck plates, handrails, flange shields, and other protective devices  removed  as  interference  immediately  after removal of machinery, piping, valves, or other system components during maintenance to prevent injury to personnel. Inspect and/or test, according to scheduled PMS and other type commander (TYCOM) requirements, all installed safety devices, alarms, and sensors. Assign a high priority to repair of defective safety devices. Cleanliness  of  machinery  and  its  spaces profoundly  affects  the  safety  of  personnel  and equipment. Correct oil leaks at their source. Wipe up spills  of  any  kind  immediately,  and  dispose  of  the 19-17 Student Notes: