By Akanimo Sampson
The world’s first international standard for oxygen reduction systems has emerged. This is a seeming good news of sorts because one of the most effective ways of preventing fires in buildings is to reduce the level of oxygen in the air.
Prevention is always better than cure, and there are few better examples than with fires. If fires can only survive when there is oxygen to fuel them, removing it from the air is an effective way to ensure that the environment remains fire-free.
Oxygen reduction systems (ORS) do that by creating atmospheres where there is not enough oxygen for a fire to break out, but enough for humans to breathe easily.
However, installing such systems can be a complex business, and requires in-depth knowledge of the space being protected, how it is used and by whom.
Currently, there are various national standards and technical guidelines in place, mainly in Europe, but what has been missing is an internationally agreed set of requirements for quality, safety and performance that everyone can use.
ISO 20338, Oxygen reduction systems for fire prevention — Design, installation, planning and maintenance, specifies minimum requirements and defines the specifications for the design, installation and maintenance of fixed oxygen reduction systems.
It applies to those systems that use nitrogen-enriched air used for fire prevention in buildings and industrial production plants, and can be used for new systems as well as for the extension and modification of existing systems.
Chair of the International Organisation for Standardisation (ISO) Technical Sub-committee that developed the standard, Alan Elder, said it will be useful to users of Oxygen Reduction Systems (ORS), such as facilities owners, as well as for meeting regulatory requirements.
“Insurance companies, manufacturers, installers and users will all benefit from ISO 20338, particularly from regions outside Europe, because it will enable them to improve the performance and safety of ORS, as well as provide a way for governments to set regulatory requirements, and for users to meet them.’’
ISO 20338 was developed by subcommittee 8, Gaseous media and firefighting systems using gas, of ISO technical committee ISO/TC 21, Equipment for fire protection and fire fighting. The secretariat of ISO/TC 21/SC 8 is held by Standards Australia, ISO’s member for Australia.
This document specifies minimum requirements and defines the specifications governing the design, installation and maintenance of fixed oxygen reduction systems with oxygen reduced air for fire prevention in buildings and industrial production plants. It also applies to the extension and modification of existing systems.
This document applies to oxygen reduction systems using nitrogen-enriched-air which are designed for continual oxygen reduction in enclosed spaces.
Nitrogen is, today, the most suitable gas to be used for oxygen reduction. For other gases, this document can be used as a reference.
This document does not apply to: Oxygen reduction systems that use water mist or combustion gases; explosion suppression systems; explosion prevention systems, in case of chemicals or materials containing their own supply of oxygen, such as cellulose nitrate; fire extinguishing systems using gaseous extinguishing agents; inertization of portable containers; systems in which oxygen levels are reduced for reasons other than fire prevention (e.g. steel processing in the presence of inert gas to avoid the formation of oxide film); and inerting required during repair work on systems or equipment (e.g. welding) in order to eliminate the risk of fire or explosion.
In addition to the conditions for the actual oxygen reduction system and its individual components, this document also covers certain structural specifications for the protected area.
The space protected by an oxygen reduction system is a controlled and continuously monitored indoor climate for extended occupation. This document does not cover unventilated confined spaces that can contain hazardous gases.