The two most-traded grades of obsolete steel scrap — HMS #1 (clean, ≥1/4" thick) and HMS #2 (galvanized/coated, mixed) — that mills consume by the rail-car load.
## What is HMS? **Heavy Melting Steel (HMS)** is the catch-all grade for prepared steel scrap that mills feed into electric arc furnaces. - **HMS #1 (ISRI 200/201):** Clean, uncoated steel ≥ 1/4" thick, sized to ≤ 60 × 24 inches. No motor blocks, no tin-coated material. - **HMS #2 (ISRI 202/203):** Mixed coated steel, sheet, light pipe, galvanized OK. Lower price than #1. ## Why it matters HMS is the **price-discovery grade** — Platts and Metal Bulletin publish a daily HMS index that everything else trades against. ## How WeighPay handles HMS WeighPay's price-list module pulls daily HMS index data, applies the operator's delta (e.g. "Index – $25/ton"), and prices every inbound load against that current number.