Dangerous Goods by Road
openings for filling, emptying and venting in the bodies or heads of non-removable head (1n1) drums
shall not exceed 7 cm in diameter. drums with larger openings are considered to be of the removable
head type (1n2). closures for openings in the bodies and heads of drums shall be so designed and
applied that they will remain secure and leakproof under normal conditions of carriage. closure
flanges shall be joined in place (welded, solded, etc.) in accordance with the technical state of the art
for the used metal or metal alloy so that the seam join is leakproof. gaskets or other sealing elements
shall be used with closures, unless the closure is inherently leakproof.