Please choose the correct ending to complete the given sentence: Health: [header] How to control environmental pollution risks in a hospital [title] Accurately record your inventory. [step] Keep careful track of the inventory of materials you have on hand in the hospital for future use. Avoid overstocking items that have limited lifespans, as these will need to be disposed of.

Ending1: Use detailed drawings or notes so you can remember information later on. [title] Make a detailed estimation of the hospital's cost to the patients. Ending2: [substeps] Before deciding to use chemicals, you can take into account the unequal number of supplies you have used. Subtract 65% every room in the hospital. Ending3: [substeps] Perform quarterly inventory checks to look for items that are close to the end of their lifespans. A computerized inventory system will make this task much easier. Ending4: [substeps] Take inventory that ranges from 500 to 800 pounds a day. In a hospital setting, do not attempt to do the same.

Answer format: ending1/ending2/ending3/ending4