Needle Angles: Standard medication doses for adults are to be rounded to the nearest tenth (0.1) of a milliliter. The standard 3-mL syringe is calibrated in tenths of a milliliter. The nurse should not administer more than 3 mL per intramuscular or subcutaneous injection site; when a volume greater than 3 mL is required, a 5-mL syringe, calibrated in fifths, may be used.