5. Fireplaces equipped with a closed hearth – Wood and solid mineral fuels

The provisions set out below only concern specifications and special requirements for fireplaces equipped with a closed hearth or insert, designed to use solid minerals and wood as fuel, by comparison with DTU 24.2 "Closed hearth or insert".

The essential difference is that this type of fireplace accepts solid mineral fuels in the 1 ^re category, i.e. :

• Lean solid fuels: all natural or artificial solid mineral fuels that generally produce low smoke levels in the most common appliances (class I);

• solid mineral fuels with a volatile matter index < 14% (index defined by standard NF M 03-004): processed agglomerated coal cokes known as "smokeless pellets" and "non-smoky pellets".