ATCTECH AIMS TO BE YOUR RELIABLE SOURCE FOR DISPOSABLE NITRILE EXAMINATION GLOVES
CRANBERRY KIMBERLY-CLARK HARTALEGA TOP-GLOVE SRI-TRANG & BIOTECH
NITRILE is a synthetic rubber material that offers chemical and abrasion resistance and is a very good general-duty material for gloves. Nitrile rubber, also known as NBR, Buna-N, and acrylonitrile butadiene rubber, is a synthetic rubber copolymer of acrylonitrile (ACN) and butadiene. Trade names include Perbunan, Nipol, Krynac and Europrene.
Glove materials are evaluated on three criteria when exposed to chemicals:
- Breakthrough time: This is how long it takes to detect a substance inside the glove when the outside is exposed to a chemical. A glove that holds ups for greater than eight hours is considered excellent.
- Degradation: This refers to the physical changes in the material such as swelling, cracking, softening or shrinking, which occur when it comes in contact with a chemical. A glove can exhibit chemical breakthrough even if it doesn’t show signs of degradation.
- Permeation rate: This is the rate at which a substance passes through a glove material once breakthrough takes place. This rate includes absorption on the surface, diffusion through the material, and desorption on the inside surface.
It is important to remember that laboratory testing data does not take into account the effects of hand movement and body temperature. The actual protection will be less for a glove that is being worn and stressed during use.
Optimizing Glove Protection
Selecting the right thickness
Glove thickness is usually given in the unit mils, which is equal to one one-thousandth of an inch; therefore, a glove that is 10 mil, is 0.010 inches thick. A thicker gauge glove will provide more protection than a thinner glove of the same material, but often at the expense of touch-sensitivity and dexterity.
Double-gloving can be used to increase the total breakthrough time of a particular glove, but this increases hand fatigue and overheating and is recommended only for short-duration tasks.
Selecting the right size
A glove that is too small for your hand will be over-stretched, which stresses the material and makes it less protective. A glove that is too large may compromise dexterity and may also become more easily damaged during use. Use the manufacturer’s size chart to choose an appropriate fit.
Removing gloves carefully
Glove removal (or “doffing”) must be done carefully to avoid contact with the outside of the glove. This video from UCLA demonstrates two methods of proper glove removal: https://www.youtube.com/watch?v=dyLEd9cng5U
Avoiding cross-contamination
Soiled gloves can contaminate objects and surfaces, later exposing you to chemical hazards. When this occurs, you can unknowingly be exposed to chemical hazards. If you do experience an acute health effect, it can be difficult to determine which chemical was the source of the exposure.
Reduce the likelihood of cross contamination by:
- changing gloves immediately when contaminated and after each chemical-handling task
- discarding gloves immediately after use. Never reuse disposable nitrile gloves!
- removing gloves and washing hands before leaving the lab
- establishing designated glove-only vs. no-glove items such as pens, keyboards, instruments, drawers, door handles, refrigerators, and work spaces
Do not wear gloves in hallways, offices, break rooms, elevators, restrooms, or any other public areas!
A Note about Allergies
In addition to their superior chemical resistance profile, another reason that nitrile gloves are used instead of latex in Penn research labs is to avoid the skin allergies that can be caused by the proteins in the latex rubber. It is possible, however, for some individuals to be sensitive to the accelerators (chemical additives) in nitrile.
Accelerator-free nitrile glove products are available for people who have sensitivity to standard nitrile gloves. One example is pictured here: Hourglass International™ HandPRO™ FreeStyle1100 Nitrile Exam Gloves
This fact sheet provides some general guidelines about the compatibility of nitrile rubber with common lab chemicals. You can print a PDF of the compatibility information to post in your lab. Posting this information is not a requirement. The attachment can be downloaded from the link at the bottom of this Fact Sheet.
In general, nitrile rubber provides short-term splash protection against the following chemicals. Breakthrough will not occur in under 15 mins for a 5-mil or greater thickness glove.
Medical Gloves For Single Use – Why These Standards?
In Europe, these standards are used to secure the glove wearer and the patient from cross contamination.
EN 455-1: Medical gloves for single use – Part 1: Requirements and testing for freedom from holes
EN 455-2: Medical gloves for single use – Part 2: Requirements and testing for physical properties
EN 455-3: Medical gloves for single use – Part 3: Requirements and testing for biological evaluation
EN 455-4: Medical gloves for single use – Part 4: Requirements and testing for shelf life determination
The following will in short terms describe each standard, and why it is important.
EN 455-1: Medical gloves for single use – Part 1: Requirements and testing for freedom from holes
This standard describes the test method in details how the gloves should be tested for freedom from holes. It is done via a watertight test, where the gloves are filled with 1 liter of water. After a specific time, the gloves are checked, and they must meet an AQL of min. 1,5 to prove compliance with this standard. That means only a certain level of pinholes is allowed in the gloves if it is CE labelled as a medical glove.
Why Is EN 455-1 Important:
This standard is important because we expect the glove we wear to be a barrier. If the gloves have a lot of pinholes, this barrier is compromised, and we are no longer protected from cross-contamination. Some people would be surprised to find out that there are some gloves that could have a pinhole. Since medical gloves are mass-produced, it is impossible to manufacture gloves without failures. Gloves are tested during production and before shipment (not all are doing that, but it can be required). It is important that the minimum level of pinholes are kept, as the risk of getting an infection through the glove will be increased with a higher AQL level (you can read more about AQL levels in the INFO – AQL).
Therefore, to ensure that the purpose of the standard is met the AQL cannot be higher than 1,5, if you want to have a safe glove.
EN 455-2: Medical gloves for single use – Part 2: Requirements and testing for physical properties
In this standard, you will find the requirements for the size of the glove and the strength of the glove.
This means exactly that you will find a table that describes the min. requirements for the length and the width of a surgical glove, and you will find another with the same information for examination and procedure gloves.
There are also requirements to the strength of the glove, or more precisely how much force needs to be used before the glove breaks – the Force at Break.
These requirements are different for different types of material, as well as it is different for surgical gloves and examination/procedure gloves.
The test method is described in details, and the gloves must be tested after manufacturing and after a challenge test.
Why Is EN 455-2 Important?
This standard is important to make sure that when you take out a Medium glove from a dispenser, that this glove would not be a size Small in another brand. It is also important that the gloves are manufactured with a certain length, enabling the whole hand to be covered.
The strength of the glove is important to make sure that the glove does not tear when you done the glove and if you use it for the intended purpose. The challenge test proves that the material under certain parameters will keep the strength.
EN 455-3: Medical gloves for single use – Part 3: Requirements and testing for biological evaluation
This standard describes different areas that are important to make a biological evaluation on the gloves. It is the most complicated of the 4 standards, because there are many different test methods mentioned and different requirements.
A lot of manufacturers still believe this standard is only for latex glove, because here the latex protein level is covered, but because there are a lot of other issues covered by this standard, it is relevant for all types of Medical gloves.
There are various tests that must be made.
First there is the biological evaluation to see whether the glove will increase the risk of getting sensitized or is an irritant to the wearer. This is done by using 2 different parts of ISO 10993. The parts where the test methods are described are ISO 10993-5 and ISO 10993-10. Why these standards are used are based on the evaluation form ISO 10993-1, where a glove is found to be used on the surface of the skin, and in a shorter time.
The protein level of a latex glove should be tested using the modified Lowry test There are no requirements for a minimum protein level in this standard. Other test methods for protein level are mentioned in the annexes of this standard.
The powder level of a powder free glove should be tested using the method described in ISO EN 21171. The powder level of a powder free glove cannot exceed 2 mg/glove. If the powder level is above that, the glove is considered a powdered glove
Endotoxin level of a sterile glove can be tested. If you want to label your glove with a low content of endotoxin, the level must be below 20 EU/pair of gloves (EU=Endotoxin Units).
There are also labelling requirements in this standard, both specific for gloves, but reference to EN ISO 15223-1 is drawn.
When a manufacturer claims compliance to this part of EN 455, they must inform a user, if there are any chemicals added that are known to cause adverse health effects – upon request.
EN 455-3 may seem complicated, but it just covers what is needed to make sure the glove has undergone a proper biological evaluation before it is sold.
Why Is EN 455-3 Important?
It is important because we want to make sure that the glove does not make you sick, when you wear it. You should not be sensitized by using it, and irritants should be so low as possible.
There will always be a risk of reacting to your glove, this risk must be low. If you react to your glove, you need to be able to find out, which glove to use instead. Here the standard also helps you, because you can ask for a list of the chemicals used in the glove.
EN 455-4: Medical gloves for single use – Part 4: Requirements and testing for shelf life determination
All glove has a certain shelf life. They need to be able to meet the first 3 mentioned standards during their shelf life. Therefore, this standard describes how to test the shelf life of a glove, and how it should be labelled. There are 2 test methods. The first one is the accelerated shelf life determination. The glove is undergoing different challenge tests and based on the results of the test the theoretical shelf life is calculated. When the shelf life determination is done based on the accelerated tests, the maximum years that can be claimed is 3 years. This test is normally made when a new glove is introduced. At the same time, it is a must that the real-time shelf life determination is started. This will take years to finalize – up to 5 years as this is the maximum shelf life for a glove.
Why Is This Standard Important?
It is important that when you use the glove, that you know whether it still provides you the expected protection. Since a glove degrades over time, it will only last for a certain period, when it is stored correctly.
You should not use the glove after the expiry date, as it may not give you the expected protection any more.
The Right Glove For the Task
On-the-job barrier performance of exam gloves can differ, depending on the glove material and the task at hand. Consider the benefits and limitations of these materials when selecting exam gloves for each situation:
| Natural Rubber Latex | Nitrile | Vinyl | Polychloroprene | |
| Puncture resistance/durability |  | | | |
| Comfort and tactile sensitivity | | | | |
| Resistance to chemo drugs and chemicals | | | | |
| Cost | $$ | $$ | $ | $$$ |
| Risk of Type 1 allergic reaction |  |
With its balanced properties, affordable cost and no risk of latex allergies, Nitrile has become the #1 exam glove material in the healthcare industry.
IMPORTANT FACTORS TO CONSIDER – ASTM STANDARDS
ASTM standards can help you determine if your glove has the properties you need for each application. The standards for nitrile exam glove characteristics are contained in ASTM D6319-10.1
- Powder-free. Powdered exam gloves are banned by the FDA as of January 18, 20172 because they present a substantial risk to patients and healthcare workers. Make sure all exam gloves are powder-free.
- Thickness (ASTM D3767). Choose glove thickness based on the level of risk. Thicker gloves are generally more protective but offer less comfort and tactile sensitivity.
- Length. Choose longer gloves when the area of exposure is wider or unknown or there is a risk of channeling (fluids flowing down between the gown cuff and the glove).
- Tensile Strength (ASTM D412). Aim for high tensile strength (the amount of force applied to a glove until it breaks, normalized for thickness). Also consider the force at break, which is not normalized for thickness. This gives you a better reading of glove durability.
- Ultimate Elongation (ASTM D412). Look for a high level of stretch so gloves give rather than break when stressed or snagged during a procedure.
KNOW ABOUT TESTING STANDARDS
A wide range of tests help determine the usability of exam gloves in different environments and procedures.
- Water Leak test (ASTM D5151) fills gloves with water to detect holes that compromise protection. Aim for the lowest possible value: AQL of 1.0 or lower.3
- Viral Penetration (ASTM F1671-97b) – be sure the gloves you choose have successfully passed this test.
- Chemotherapy Drugs testing clears gloves for this special use. The chemotherapy gloves you select should be tested per the latest standard (ASTM D6978-05) using a wide range of chemotherapy agents. Breakthrough times should be listed on the dispenser box.
1 The standards for exam gloves characteristics are contained in ASTM D3578-05 for natural rubber latex and D5250-06 for vinyl.
2 https://www.federalregister.gov/documents/2016/12/19/2016-30382/banned-devices-powdered-surgeons-gloves-powdered-patient-examination-gloves-and-absorbable-powder
3 The ASTM standard allows for an AQL of maximum 2.5 for exam gloves.
A Guide To Glove Safety: EN 374
Working with chemicals is very high risk, which means that you need to make sure that you buy the right pair of chemical-resistant gloves. Chemical-resistant gloves are tested to a standard called EN 374, a standard that informs the wearer about what chemicals the gloves are designed for use with and for how long. This guide will provide the details of EN 374, helping you to purchase your right pair of Chemical-Resistant Gloves.
Back to Basics: What Is EN 374?
EN 374 is a chemical-resistant glove standard that was last modified in 2016. It has wide scope, testing a glove’s response to a wide range of chemicals while taking into account permeability, breakthrough time, shrinkage and more. The standard is divided in five sections which can be viewed below:
- EN 374 – 1: Protective Gloves Against Chemicals and Micro-Organisms
- EN 374 – 2: Determination to Resistance to Penetration
- EN 374 – 3: Determination of Resistance to Permeation by Chemicals (replaced by EN 16523)
- EN 374 – 4: Determination of Resistance to Degradation by Chemicals
- EN 374 – 5: Terminology and Performance Requirements for Micro-Organism Risks
In the next section we go into each section in further detail. We describe the details of each point and why each section is important for you.
SPECIFICATIONS: WHAT WILL AN EN 374 GLOVE ACHIEVE?
Your chemical-resistant glove can be awarded any from EN 374 – 1, 2, 3, 4 and 5. You can view each section in detail below:
EN 374 -1:
Protective Gloves Against Chemicals and Micro-Organisms
Most chemical resistant gloves will be tested to EN 374 – 1. EN 374 – 1 will test your gloves to a total of 18 different chemicals before awarding them with a certification of either A, B or C depending on how resistant the glove is to chemicals. Finally, this standard also includes a logo that quickly informs the user of which chemicals the glove can be used with.
Firstly, the gloves will feature a logo on their back that includes the Type and the chemicals that you can use the glove with. The letters correlate to a chemical that can be identified in the table below the logo. Finally, the type corresponds to the information below the chemical table.
Logo Informing the Chemical Properties of a Glove
| Chemical | Code Letter |
|---|---|
| Methanol | A |
| Acetone | B |
| Acetonitrile | C |
| Dichloromethane | D |
| Carbon Disulphide | E |
| Toluene | F |
| Diethylamine | G |
| Tetrahydrofuran | H |
| Ethyl Acetate | I |
| n-Heptane | J |
| Sodium Hydroxide 40% | K |
| Sulphuric Acid 96% | L |
| Nitric Acid 65% | M |
| Acetic Acid 99% | N |
| Ammonoim Hydroxide 25% | O |
| Hydrogen Peroxide 30% | P |
| Hydroflouric Acid 60% | S |
| Formaldehyde | T |
- Type A: Protective glove with permeation resistance of at least 30 minutes with at least six test chemicals
- Type B: Protective glove with permeation resistance of at least 30 minutes with at least three test chemicals
- Type C: Protective glove with permeation resistance of at least 10 minutes with at least one test chemical
EN 374 -2:
Protective Gloves Against Chemicals and Micro-Organisms Determination to Resistance to Penetration
EN 374 – 2 can be identified by the standard below. It is designed to determine a gloves resistance to penetration by chemicals, something that is identified by testing the gloves to leakage when air and water is pressed through the gloves. The gloves are inner-pressured, filled with air or water before being measured for leakage afterwards.
Under EN 374 – 2 a glove can achieve three different results:
- EN 374 – 2: 1 – Waterproof
- EN 374 – 2: 2 – Waterproof / Micro-Organism Resistant
- EN 374 – 2: 3 – Waterproof / Micro-Organisms Resistant
A glove will show this symbol if it is resistant to water and air leakage
EN 374 -3:
Protective Gloves Against Chemicals and Micro-Organisms: Determination of Resistance to Permeation by Chemicals
EN 374 – 3 has been replaced by EN 16523-1.
EN 374 -4:
Protective Gloves Against Chemicals and Micro-Organisms: Determination of Resistance to Degradation by Chemicals
EN 374 – 4 is designed to take into account how long it will take for a glove to degrade. Degrading can be caused by:
- Degradation (Change in a glove material)
- Degradation can cause brittelness, swelling or shrinkage
- A standardised measurement method for degradation for the first time
EN 374 -5:
Protective Gloves Against Chemicals and Micro-Organisms: Terminology and Performance Requirements for Micro-Organism Risks
The final part of EN 374 is EN 374 – 5, which describes if a glove is suitable for use with biological agents. The two parts of the standard are represented by two symbols which can be viewed below. The only criteria in terms of results for this standard are if the gloves achieve the standard, or if they do not.
 Symbol Designating Gloves with Fungi and Bacteria Resistance |  Symbol Designating Gloves with Fungi, Bacteria and Viral Risks |
ALL YOUR QUESTIONS ON EN 374 ANSWERED
Below are the questions that we get from customers most often regarding EN 374.
How Do I Know What Chemicals I Can Use a Glove With?
The below symbol can be found on the conformity statement or on the back of your gloves. The letters beneath the symbol allow you to identify which chemicals you can use the gloves, and you can find out which chemicals are relevant via the Chemical Resistance Guide.
The letters allow you to identify which chemicals you can use the gloves with
How Do I Know How Long the Gloves Will Stay Chemical Resistant?
In the image above you can see that those gloves achieve a Type A status. Gloves can either achieve Type A, B or C, something you will be able to identify via the symbol either on the gloves on the case or on the supplied conformity statement. The different types stand for:
- Type A: Protective glove with permeation resistance of at least 30 minutes with at least six test chemicals
- Type B: Protective glove with permeation resistance of at least 30 minutes with at least three test chemicals
- Type C: Protective glove with permeation resistance of at least 10 minutes with at least one test chemical
Do All Gloves Have a Level of Chemical Resistance?
No, not all gloves have a level of chemical resistance. However, plenty do, and you can find niche chemical gloves in our list below:
- Anti Static Chemical Gloves
- Cut Resistant Chemical Gloves
- Glass Handling Chemical Gloves
- Oil Resistant Chemical Gloves
- Nitrile Chemical Gloves
Can Disposable Gloves Be Chemical-Resistant?
Yes, we sell plenty of chemical resistant disposable gloves. They are most common in Nitrile, as nitrile tends to be better resistant to chemicals, oils, waters and grease.
How Safe Are EN 374 Rated Gloves?
EN 374 gloves can be trusted because they are certified by an independent European body that was set up by the European Union to ensure a high standard in glove safety. The standards are back up by strong and resilient tests that are among the most intrusive in the world, meaning that the end results are as strong as you can expect them to be.
Where Can I Buy an EN 374 Rated Glove?
We sell a wide range of Chemical Resistant Gloves. Alternatively, you can view our Chemical Resistant Guide Below:
| Chemical |
|---|
| Methanol |
| Acetone |
| Acetonitrile |
| Diethylamine |
| Tetrahydrofuran |
| Ethyl Acetate |
| n-Heptane |
| Sodium Hydroxide 40% |
| Sulphuric Acid 96% |
| Nitric Acid 65% |
| Acetic Acid 99% |
| Ammonoim Hydroxide 25% |
| Hydrogen Peroxide 30% |
| Hydroflouric Acid 60% |
| Formaldehyde |
Buy the Right EN 374 Gloves
We hope that this guide has given you a better idea of the type of EN 374 Gloves that are ideal for you. It’s important to take your time, as a mistake in purchase can mean that you end up with gloves that are resistant to an irrelevant chemical.
CE Category Information
Personal Protective Equipment Directives (89/686/CEE) and (93/68/CEE) have been put in places by the European Community to ensure all regulations regarding testing of all PPE sold within the community works together. All gloves of intermediate and a more complex design must now be tested independently to grade their performance and ensure their safety to the user. It is a requirement that if they meet these standards, a CE Mark is visible on the gloves or their packaging when it is not practical.
CE Category I
Simple Design – for minimal risks only. Suitable only for low risk applications where hazards can be identified by the wearer in time to deal with them.
CE Category II
Intermediate Design – reversible risks. Products are type examined by an approved body where they examine the manufacturers’ technical specifications and conduct tests for the relevant standards to ascertain their conformity and/or performance.
CE Category III
Potentially fatal risks, for example in activities where toxic or highly corrosive chemicals are handled. The glove must meet the standards set out for this category. Its compliance is not only certified but also checked by a notified body, the reference number of which is located below the CE logo.
GLOVE FACTORY PRODUCTION LINE
