BS 8485:2015+A1:2019

What is BS 8485 - Methane and carbon dioxide ground gases about?  

BS 8485 is a British standard on code of practice for the design of protective measures for methane and carbon dioxide ground gases for new buildings 

BS 8485 gives recommendations on ground gas site characterization and the choice of solutions for the design of integral gas protective measures for new buildings to prevent the entry of carbon dioxide and methane, and provide a safe internal environment. 

BS 8485 gives a process that can be used to demonstrate that risks posed by the potential or actual presence of carbon dioxide and methane have been addressed. 

Note: BS 8485 does not cover the protection of new buildings against other hazardous ground gases. Nor does this British Standard cover protection of buildings into which methane and carbon dioxide might be introduced by the activities for which they are used. 

Who is BS 8485 - Methane and carbon dioxide ground gases for? 

BS 8485 on methane and carbon dioxide ground gases is useful for: 

• Designers of gas protection measures 
• Regulators involved in the assessment of design solutions 
• Constructors 

Why should you use BS 8485 - Methane and carbon dioxide ground gases?  

Toxic, asphyxiating and flammable and potentially explosive ground gases can enter buildings and other structures on and below the ground, they pose potential risks to occupants and users, and to the structures themselves. 

BS 8485 is intended to be used by designers of gas protection measures and by regulators involved in the assessment of design solutions. It recognizes that there are a number of factors requiring consideration which affect the sensitivity of a development to the effects of ground gas, and that there is a range of design solutions available for different situations. 

It is anticipated that specialist advice is needed in the assessment of the ground gas data and in the risk assessment phase, BS 8485 will help you evaluate these. 

What’s changed since the last update?  

BS 8485:2015 superseded BS 8485:2007, which has been withdrawn. BS 8485:2015+A1:2019 supersedes BS 8485:2015, which is withdrawn. 

BS 8485:2015+A1:2019 a full revision of the standard, and introduced the following principal changes: 

• Inclusion of more detailed recommendations on the interpretation of gas monitoring data and assignment of the gas screening value. 
• Inclusion of four building type definitions and amendments to the gas protection scores recommended for different characteristic situations. 
• Inclusion of recommendations for reporting of gas protection measures at the design, installation and post-construction (verification) stages. 
• Inclusion of worked examples of solution choices for a range of different ground gas conditions and building types. 
• Revision of recommendations on the design of ventilation protective measures