Respiratory protective devices for self-rescue. Filtering devices with hood for escape from fire. Requirements, testing, marking Ingestion-build-190310 The specific nature of openness

The specific nature of openness for a system is defined by all the following properties:

BS 2838-2 applies to couches fitted with an adjustable head section that is suitable for use in hospitals

BS 975 gives examples of the use of a BS hydrometer

in definite proportions to achieve a uniform mixture with desirable physical and chemical properties for low-temperature processing

Distillation is the most widely used separation technique in the petroleum industry

Respiratory protective devices for self-rescue. Filtering devices with hood for escape from fire. Requirements, testing, marking Ingestion-build-190310 The specific nature of openness