Last checked by Coal Boss
Coal in a heap, wagon or truck is never uniform — lumps and fines, wet and dry patches. Sampling means collecting many small portions (increments) from across the lot so that the final sample represents the whole of it.
The collected sample is then crushed, mixed and divided down to a small laboratory portion, which is tested. In India, methods for sampling coal are set out in the Bureau of Indian Standards' IS 436, and methods of testing in IS 1350.
Because the sample stands in for hundreds of tonnes, where and how it was taken — and who witnessed it — matters as much as the lab itself. Many buyers and sellers agree on a referee sample and a third-party lab in advance.
What it means if you trade coal
Keep the sampling details with the lab result: which lot, where it was taken, by whom, and which lab tested it. When a customer disputes quality, that record is what settles it.
Hinglish mein, short mein
Sampling matlab poore lot mein se jagah-jagah se chhote hisse lena, taaki sample poore maal jaisa ho; phir use kootkar, milakar, chhota karke lab mein test karte hain. India mein tareeka: sampling ke liye IS 436, testing ke liye IS 1350. Quality ke zyadatar jhagde isi pe aate hain ki sample kahan aur kaise liya — isliye ye details result ke saath rakhiye.
Sources
- StandardBureau of Indian Standards — IS 436 Part 1/Sec 1 (Manual sampling of coal)
- StandardBureau of Indian Standards — IS 1350 Part 1
Coal Boss explanation, based on the sources above.
