Answer- Kiln drying is a process in which firewood is force-dried in large chambers to reduce moisture, which happens much faster than air-drying fresh cut logs. 

To comply with the government’s Ready to Burn legislation, and accreditation run by Woodsure, logs must be dried down to below 20% moisture content. It is now (as of Nov 2022) against the law in England (and soon to include Scotland and Wales) to sell firewood that does not meet these standards and carry the relevant accreditation by the supplier and shown on all packaging. 

It is important to note that kiln dried logs do not guarantee moisture content below 20% moisture content, but the ‘Ready to Burn’ logo should.To ensure you have properly dried logs, you can test the logs yourself using a moisture meter, splitting the log in the middle to measure the internal reading.