A method of employing ethylene oxide (EtO) to sterilize a prefilled syringe assembly without adversely affecting the contents of the prefilled syringe assembly, comprising: assembling a syringe assembly that comprises a plunger and a non-glass barrel, the method including: inserting the plunger into the barrel at a second end of the non-glass barrel to define a chamber therein; filling the non-glass barrel with sterilization sensitive material at a first end of the non-glass barrel, the sterilization sensitive material one of saline, heparinized saline, and lidocaine; inserting a tip cap at the first end of the barrel to seal the sterilization sensitive material within the barrel; performing at least one ethylene oxide (EtO) sterilization procedure cycle of the assembled syringe assembly, wherein the sterilization procedure cycle comprises undergoing a preprocessing stage including raising the temperature and humidity of a preconditioning area into which the syringe assembly is located to a predetermined level to initiate growth of microorganisms and where the temperature is within the range of 32.22222222 °C - 54.44444444 °C (90-130 °F), and where the humidity is within the range of 45-95%, a wash and conditioning stage after the preprocessing stage including moving the syringe assembly to the sterilization chamber, sealing the sterilization chamber and raising the temperature to a conditioning temperature within a range of 29.44444444 °C - 54.44444444 °C (85-130 °F), and an EtO sterilization stage after the wash and conditioning stage, wherein the EtO sterilization stage comprises introducing EtO gas into a sterilization chamber containing the prefilled syringe assembly until reaching a predetermined pressure level within the range of 36,2343587333337 kPa - 67,727773333334 kPa (10.7-20 inHgA); evacuating the EtO gas by applying a vacuum pressure of approximately 20,3183320000002 kPa (6 in HgA); and wherein upon completing the EtO sterilization procedure cycle, a resultant pH of the sterilization-sensitive material is between 4.5-7.0. inserting the plunger into the barrel at a second end of the non-glass barrel to define a chamber therein; filling the non-glass barrel with sterilization sensitive material at a first end of the non-glass barrel, the sterilization sensitive material one of saline, heparinized saline, and lidocaine; inserting a tip cap at the first end of the barrel to seal the sterilization sensitive material within the barrel; performing at least one ethylene oxide (EtO) sterilization procedure cycle of the assembled syringe assembly, wherein the sterilization procedure cycle comprises undergoing a preprocessing stage including raising the temperature and humidity of a preconditioning area into which the syringe assembly is located to a predetermined level to initiate growth of microorganisms and where the temperature is within the range of 32.22222222 °C - 54.44444444 °C (90-130 °F), and where the humidity is within the range of 45-95%, a wash and conditioning stage after the preprocessing stage including moving the syringe assembly to the sterilization chamber, sealing the sterilization chamber and raising the temperature to a conditioning temperature within a range of 29.44444444 °C - 54.44444444 °C (85-130 °F), and an EtO sterilization stage after the wash and conditioning stage, wherein the EtO sterilization stage comprises introducing EtO gas into a sterilization chamber containing the prefilled syringe assembly until reaching a predetermined pressure level within the range of 36,2343587333337 kPa - 67,727773333334 kPa (10.7-20 inHgA); evacuating the EtO gas by applying a vacuum pressure of approximately 20,3183320000002 kPa (6 in HgA); and wherein upon completing the EtO sterilization procedure cycle, a resultant pH of the sterilization-sensitive material is between 4.5-7.0.