Changing or upgrading your cleanroom gloves is a process that requires time and due consideration. It is not to be undertaken quickly or lightly. Make the right decision and it could have a positive influence on both employee satisfaction and product/process yields. Make the wrong decision and you could be looking at hundreds, thousands, perhaps millions of dollars worth of rework, recalls and rejects if the gloves don’t perform as expected.
Did You Know?
- Even when stationary, people generate about 100,000 particles of 0.3 microns or greater. On the move, this rises to about 5 million.
- Every square inch of the human body has an average of 32 million bacteria on it.
- Every minute of the day we lose about 30,000 to 40,000 dead skin cells off the surface of our skin.
- One square inch of hand surface area has an average of 10,000 microorganisms.
- Common cleanroom contaminants include ions, non-volatile residues, outgassing, electrostatic discharge, airborne molecular contamination and microorganisms.
- Particles as small as 0.25 microns can contaminate a semicon wafer. This is equivalent to looking for a grain of salt on a football field.
Next time you’re thinking about upgrading your cleanroom gloves, consider these important tips.
- Form a selection team. Many people have a stake in the process of selecting and qualifying any new product to be used in a cleanroom. Fab/production managers, contamination control, validation engineers, QA/QC, cleanroom materials specialists, and purchasing should all play a role. In pharma and biotech cleanrooms, local safety officers must ensure that the glove will not violate any EPA or OSHA regulations or permits. Regulatory personnel will need to be involved as any changes to process may affect FDA licenses. Finally, users will be able to provide important feedback on comfort and dexterity issues.
- Carefully consider your process/products. Every cleanroom in every industry is different. Semiconductor facilities may operate at an ISO Level 3, while some medical device manufacturers may operate at ISO Level 6. Look for gloves labeled according to the cleanroom classification in which you operate. For example, some manufacturers make it easy to tell which gloves are appropriate for a Class 5 cleanroom and which can be used in a Class 3 cleanroom. But keep in mind that there are no published standards that designate gloves as a “Class 3” or “Class 5”.
If you operate in an aseptic/sterile environment, look for sterile gloves that are processed for cleanrooms but are also sterilized through gamma irradiation or other methods to reduce potential bioburden. Sterilization completely removes and/or destroys viable organisms, rendering them unable to reproduce. It is important to note that there is a difference between cleanroom sterile gloves and surgical sterile gloves. Cleanroom sterile gloves typically go through additional processing to reduce particulates and extractables from the finished product. They are packaged within a cleanroom before being sent on for sterilization. Moreover, cleanroom sterile gloves are manufactured consistent with ASTM requirements, while surgical gloves are not. Instead, they are cleared by the FDA as a medical device.
- Evaluate key performance factors. In cleanrooms, a glove’s particle and extractable counts are key and should be closely evaluated to match the cleanroom class. Refer to IEST RP-5 for recommended test procedures and guidance. Compliance with AAMI, ASTM and EN standards and regulations is also important, and some suppliers exceed the minimum performance standards set by these organizations.
Durability and tensile strength are two other important factors to consider as is barrier integrity (free of pinholes).
Some cleanroom environments – electronics, semiconductor, nanotechnology – are sensitive to static, so gloves should be evaluated for electrostatic discharge (ESD) resistance properties. Other cleanroom environments, including those in the aerospace industry, are concerned with non-volatile residue (NVR), contamination that is not easily removed from surfaces through evaporation. Gloves for these environments should be evaluated to ensure they do not contain NVR.
Comfort is also part of the performance equation. It’s simple common sense that when a glove is more comfortable (soft and stretchy like a “second skin”), users will be more likely to comply with wearing protocols. Some users may prefer the comfort of a hand-specific glove while others work well with ambidextrous gloves.
The glove’s tack level is also important. In some cases, high-tack gloves are preferred because they make it easier to hold items without the items slipping. In other cases, a slick grip is preferred for easier donning and double donning, a common practice in aseptic environments. The amount of texturing on a glove can vary from fully textured to fingertip texture. Fully textured gloves are important with ambidextrous styles, so that, no matter which glove is grabbed, the texture will be felt. Beaded cuffs are another important feature, especially for ease of donning.
A glove’s material can have a dramatic influence on both its comfort and strength. Latex gloves are typically viewed as being more comfortable, while nitrile gloves typically have strength advantages and help to avoid problems that may be associated with latex allergies. Some suppliers are using new nitrile-based production technologies to combine the comfort of latex with the strength of nitrile for gloves that provide the best of both worlds.
Sizing is another comfort factor. While most suppliers offer a range of glove sizes, some are tweaking the formula to fit a wider variety of hand sizes – for example, offering larger-size, hand-specific gloves, or gloves with extra-wide palms.
Finally, while most cleanroom gloves are designed to protect the sensitive cleanroom environment from contamination by workers, workers themselves may need protection from chemicals, acids or other hazards in the environment. Don’t forget to consider a glove’s protective properties during your evaluation.
- Demand certification. Consistently superior performance is not an option. Make sure the glove you choose is not only of the highest quality, but that it also stays within a reasonable variance of that level over time. Lot consistency should be ensured from raw materials through processing.
Acceptable Quality Level (AQL) is one piece of important data to consider. This refers to the probability of having defective gloves within a lot. The lower the AQL number, the lower the probability of defective gloves. While ASTM sets an AQL of 2.5, some glove suppliers exceed that standard to provide gloves with fewer pinholes and thus, a greater level of barrier protection.
Make sure your glove supplier can provide certificates of analysis with particle counts, extractable counts and other important data for each lot of product; trend data; specification sheets; and certificates of irradiation. Some suppliers make this information easily accessible 24/7 on their web sites, after plugging in the glove’s lot number. Actual data is better than average data, because it reflects consistency in quality manufacturing.
- The proof is in the packaging. Cleanroom design, operator procedures, correct cleaning and sanitization are critical when it comes to cleanrooms, but if incoming items are not controlled, cleaned and monitored, the contamination will walk right in. So pay special attention to how and where gloves are packaged. Are the gloves packaged in a cleanroom environment? Are they double-bagged to ensure cleanliness? The cleaner the cleanroom, the more important it is for gloves to be packaged entirely in plastic bags, including the inner wallet. Gloves for less stringent cleanrooms may use coated paper in the individual pair packages.
Sterile gloves must be suitably packaged for aseptic donning (applying the glove without breaking the sterile field). This is easier to do if the gloves come in packaging that opens properly. Sterile gloves should be packaged in pouches that open up so the left and right gloves are easily donnable.
