- SCBA may be either of the negative demand or positive pressure type or may have a changeover facility to allow operation in either mode.
- The volume of air contained in the SCBA cylinders should be at least 1,200 litres, which shall be capable of providing air for at least 30 minutes.
- Two spare charges suitable for use with the apparatus should be provided for each apparatus required.
- As a requirement approved SCBA sets must be fitted with a low pressure warning device and pressure indicator.
- Each breathing apparatus should be provided with a flexible fireproof lifeline, type approved to meet the testing standards quoted in the Marine Equipment Directive, of at least 30 m in length,The lifeline should be subjected to a test by static load of 3.5 kN for 5 minutes.
- If passenger ships carrying not more than 36 passengers and cargo ships are equipped with suitably located means of fully recharging the air cylinders free from contamination, only one spare charge is required for each apparatus required.
- On passenger ships carrying more than 36 passengers equipped with suitably located means of fully recharging the air cylinders, the required spare capacity may be reduced by one third.
- The warning device shall activate at a predetermined pressure (usually 55+/-5 bar) which will alert the user before the volume of the air in the cylinder has been reduced to no less than 200 litres.
By wearer of breathing apparatus
1 pull I am all right
2 pulls I am going ahead
3 pulls Take up my slack
4 pulls Help me out immediately
To wearer of breathing apparatus
1 pull Are you all right?
2 pulls Advance
3 pulls Back out
4 pulls Come out immediately