According to the American National Standard for Engineering Drawings, there are ten (10) different types of lines used in engineering drawings to communicate important information about the item. Some of these lines could either be thick or thin. These include the following:
Unless cylinders are firmly secured on a special carrier intended for this purpose, regulators shall be removed and valve protection caps put in place before cylinders are moved. A suitable cylinder truck, chain, or other steadying device shall be used to keep cylinders from being knocked over while in use.