What is BS 5925 – Ventilation principles and designing for natural ventilation about? 
Proper ventilation is key when it comes to ensuring indoor air is clean and free from pollutants.
BS 5925 is a British Standard that discusses the code of practice for ventilation principles and designing for natural ventilation.
BS 5925 gives recommendations on the principles which should be observed when designing for the natural ventilation of buildings for human occupation.
Note: BS 5925 does not attempt to address thermal comfort aspects of ventilation such as indoor air movement, temperature stratification, exact position of ventilation openings etc.
Who is BS 5925 - Ventilation principles and designing for natural ventilation for?  
BS 5925 on ventilation principles and designing for natural ventilation  is relevant to: 
- Manufacturers of ventilation and air conditioning system components
- Quality control and testing personnel 
- Mechanical engineers
- Building designers, planners and architects 
- Building owners/management
- Contractors
- Local authorities
Why should you use BS 5925 - Ventilation principles and designing for natural ventilation?  
Keeping your home ventilated is just as important as having a good insulation plan for cost savings and energy efficiency. A proper ventilation system helps you in maintaining improved air quality, low humidity levels, contributes toward respiratory benefits.
BS 5925 is divided into three sections, which cover general recommendations, the main reasons for the provision of ventilation and recommended quantitative air flow rates, and recommendations on the design of natural ventilation systems and the estimation of air infiltration rates in housing.
Recommendations on evaluating contamination risks, calculating ventilation rates to reduce the risk of surface condensation under steady state conditions, determining ventilation requirements, calculating reference wind speed, and calculating natural ventilation rates for a simple building are given in BS 5925.
Thus, BS 5925 helps you in the construction of an operationally efficient natural ventilation system.
