Criteria for Selecting a Sterilization Packaging system

Since the market offers many products, it is necessary to first evaluate and select the product that fulfills the majority of needs. The principal purpose of any packaging material is to hold the objects, maintain the sterility of the content, and provide an aseptic presentation. At the same time, it should be economically effective and cost-saving for the institution. The following criteria can be helpful when choosing a suitable, efficient packaging material.

Porosity / permeability

The packaging material should make it possible for the sterilizing agent to penetrate and leave the package while also providing a highly effective bacterial barrier.

The flow of air or permeability is expressed in liters per minute every 100 cm2. Air flow is necessary for ensuring the sterility of the contents in the package. A lower measure is equivalent to lower air flow and a higher measure means that the result will be better (more sterile).

Good penetration of steam and ethylene oxide, for example, allows the achievement of improved sterility conditions in the materials. On the other hand, kraft, crepe, parchment and other similar types of paper are closely woven and do not allow adequate flow of the steam or gas used.

A very simple test is to exhale cigarette smoke through an unwoven cloth and repeat the experience with a piece of paper. This will make it possible to observe the differences.


The factors that should be considered for measuring the strength of a certain type of packaging for sterilization are three: resistance to bursting, tearing and abrasion.

Burst resistance refers to possible punctures or pricks produced by the corners of instrument trays or packaged instruments.

Burst resistance is measured through the Mullen Burst Test. This test uses an apparatus with an expansive 1 ¼ rubber diaphragm that pushes the material upward progressively until it, literally, bursts. The pressure required is measured in pounds per square inch (PSI). Higher values correspond to better resistance by the material.

Tear resistance is not as important as burst resistance since the tests of tear resistance (Elmendorf Test) only measure the strength that is necessary to apply in order to propagate the tear, but once the tear has already occurred.Abrasion resistance, on the other hand, is very important in two aspects: the resistance that the material offers to abrasion; and lower release of lint or microparticles. If the sterilization packaging wears away with friction, the material weakens and is more vulnerable to holes and tears.

Lint or particles

A product or material that does not release lint should be selected. Lint microparticles should be minimized in areas where patients undergo surgical procedures.

Sterilization packaging made from materials with high lint release is a potential risk for patients since lint serves as a vehicle for transmitting microorganisms. If lint penetrates a patient’s critical tissues, it will cause a foreign body reaction. If it penetrates the bloodstream, it can cause an embolism. As mentioned earlier, abrasion is an important source of lint. Another source is the mechanical extraction of fibrous elements. For example, removing the tape that seals the package produces lint release. The ideal is a material that has a zerocoefficient for microparticle or lint release.


Sterilization packaging should be repellent to liquids such as water or saline solution. This is in order to prevent its penetration by liquids and to maintain the contents.

The normal test to measure the degree of repellency is the Mason jar test, which simulates critical use. The capacity of penetration by liquids into the material is tested by placing saline solution in a glass jar (Mason jar) and covering the mouth of the jar with the material being examined. The bottle is then inverted over a glass base and the time required by the liquid to penetrate the material is measured.

A longer amount of time, measured in minutes and seconds, is equivalent to a more efficient protective barrier. At least 30 minutes are required in order to be considered acceptable.

In addition to water repellency, the packaging should demonstrate resistance and repellency to alcohols. This aspect should be considered since the most commonly used solutions in hospitals contain alcohol.

A very common procedure consists of placing three drops of an alcohol solution on the material. After five minutes, the material is observed to see if there has been penetration. The initial solution should not contain alcohol; then it should increase by 10% alcohol for every five minutes of exposure. Alcohol repellency is measured in the solution with the highest percentage of alcohol that does not penetrate the cloth within a period of five minutes. A solution with 70% alcohol (range 7) for five minutes is considered acceptable.


Once the package has been processed and is ready to be opened in the sterile area, the opening process should be both easy and maintain the asepsis of its contents.

All packaging has memory, or the ability to remain where it is placed. During its opening, the extremes of the packaging should remain where they are placed, without the edges caving in onto the content of the package (bad memory).

Ease of handling

Unwoven packaging materials should be easy to handle during all of the processes related to their use. The material should be soft, ductile and permit packaging without resistance. Softness is important for preventing irritation of the skin of the professional who handles many packages per day. Materials that are hard and have low ductility have sharp edges that can cause small cuts, which constitute a source of contamination both for the professional and for the patient.

Wednesday, September 13, 2023


Sterilization manual for health centers. Silvia I. Acosta-Gnass,Valeska de.

Please Check out file at the following link

General Principles of Packaging

Preparing and packaging materials

Cleaning Your Sterilizer

Ultrasonic washer

Central sterile services department (CSSD)