BS 8547:2016 pdf free.Respiratory equipment – Breathing gas demand regulator used for diving to depths greater than 50 metres – Requirements and test methods.
BS 8547 This British Standard specifies minimum performance requirements for diver carried breathing gas demand regulators for open-circuit and saturation gas reclaim systems used for diving to depths greater than 50 m.
This British Standard defines additional requirements for breathing performance and helium compatibility to those already given in 85 EN 250 and
BS EN 15333-1.
NOTE The basic requirements for diving apparatus and demand regulators as per 85 EN 250 and 85 EN 15333-1 have been retained. The exception here is for the breathing performance which is revised in this British Standard to cover the requirement for use at depths greater than 50 m.
This British Standard specifies a test method for helium compatibility with a demand regulator and a test method for measuring the work of breathing (WOB) and respiratory pressures of a demand regulator.
This British Standard does not cover auxiliary emergency breathing systems; they are covered in BS EN 250:2014, Annex B.
Normative references
The following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
BS EN 132, Respiratory protective devices — Definitions of terms and picto grams BS EN 250:2014, Respiratory equipment — Open-circuit self-contained compressed air diving apparatus — Requirements, testing, marking
BS EN 12021, Respiratory equipment — Compressed gases for breathing apparatus
BS EN 15333-1:2008, Respiratory equipment — Open-circuit umbilical supplied compressed gas diving apparatus – Part 1: Demand apparatus
Terms and definitions
For the purposes of this British Standard, the terms and definitions given in BS EN 132 and the following apply.
work of breathing (WOB) external work expended during one breath divided by the tidal volume of that breath, measured in Joule per litre.
NOTE 1 This is equivalent to volume average respiratory pressure (kPa). This WOB is, in general, proportional to the area bounded by a pressure volume diagram. Work associated with positive pressures during inhalation does not count towards the total WOB.BS 8547 pdf download.