Protective gloves play a crucial role in safeguarding workers from various hazards in the workplace. The EN374 standard has become the cornerstone for evaluating and certifying the performance of protective gloves against chemicals and microorganisms. This comprehensive guideline impacts manufacturers, safety professionals, and end-users alike, ensuring that EN 374 gloves meet stringent quality and safety requirements.
This guide aims to break down the complexities of EN374, shedding light on its various components. Readers will gain insights into EN374-1, which deals with chemical resistance, as well as explore EN374-2, EN374-4, and EN374-5. Additionally, the article will delve into EN 16523-1, formerly known as EN374-3, to provide a complete understanding of this vital standard. By the end, you will have a solid grasp of the protective glove standard, enabling you to make informed decisions on the matter.
Overview of EN374 Standard
Definition and purpose
The EN374 standard, officially known as EN ISO 374:2016+A1:2018, is a set of regulations established by the European Union to assess the performance of protective gloves when exposed to chemicals and microorganisms. This standard has become essential in ensuring that gloves provide sufficient protection against chemical hazards and biological risks, which can have profound health implications if not properly managed.
The primary purpose of EN374 is to guarantee consistency in testing and help users and safety professionals determine their chemical protection needs. It serves as a cornerstone for evaluating and certifying the performance of protective gloves, impacting manufacturers, safety experts, and end-users alike.
Key components of EN374
The EN374 standard comprises five distinct parts, each focusing on a specific type of testing and application:
- EN 374-1: Performance requirements for chemical risks
- EN 374-2: Determination of resistance to penetration
- EN 16523-1: Determination of material resistance to permeation by chemicals (formerly EN 374-3)
- EN 374-4: Determination of resistance to degradation by chemicals
- EN 374-5: Protection against bacteria, fungi, and viruses
These components work together to provide a comprehensive evaluation of protective gloves. Gloves are categorized based on their performance in these tests, ensuring that users can make informed decisions about hand protection in their workplace.
Recent updates and revisions
The EN374 standard has undergone significant changes in recent years to enhance its effectiveness and address evolving safety concerns. The most notable update occurred in 2016, resulting in the current version, EN ISO 374:2016.
Key changes in the updated standard include:
- Expanded chemical testing: The number of test chemicals has increased from 12 to 18, adding six new categories to the permeation table. This expansion allows for a more comprehensive assessment of glove performance against a wider range of chemical hazards.
- New classification system: The updated standard introduces a new categorization system, classifying gloves as Type A, Type B, or Type C based on their level of protection:
- Type A: Provides permeation resistance of at least 30 minutes for at least 6 test chemicals
- Type B: Offers permeation resistance of at least 30 minutes for at least 3 test chemicals
- Type C: Demonstrates permeation resistance of at least 10 minutes for at least 1 test chemical [1]
- Introduction of degradation testing: EN 374-4:2013 was added to the standard, introducing a new degradation test. This test evaluates changes in the physical properties of gloves after exposure to specific chemicals, such as swelling, cracking, brittleness, or shrinkage .
- Updated pictograms: The revised requirements are reflected in new pictograms that appear on certified gloves and glove dispenser boxes, providing users with clear visual indicators of protection levels .
These updates have strengthened the EN374 standard, making it more comprehensive and better equipped to address the diverse range of chemical and microbiological hazards encountered in various industries. The changes aim to provide users with more detailed information about glove performance, enabling them to make more informed decisions when selecting appropriate hand protection.
As the standard continues to evolve, it remains crucial for users and safety professionals to stay informed about the latest updates and their implications for workplace safety. Regular consultation with manufacturers and occupational safety experts is recommended to ensure that the chosen EN 374 gloves meet the specific requirements of individual work environments.
Understanding EN374-1: Chemical Resistance
EN374-1, a crucial component of the EN374 standard, focuses on evaluating the performance of protective gloves against chemical risks. This section of the standard has undergone significant changes to enhance its effectiveness in assessing glove resistance to various chemicals.
Type A, B, and C classifications
The updated EN374-1 introduces a new classification system that categorizes gloves into three types based on their permeation performance. This system helps users quickly identify the level of protection offered by a particular glove:
- Type A: These gloves provide the highest level of protection, demonstrating permeation resistance of at least 30 minutes for a minimum of six test chemicals.
- Type B: Offering a moderate level of protection, Type B gloves show permeation resistance of at least 30 minutes for a minimum of three test chemicals.
- Type C: The basic level of protection, Type C gloves exhibit permeation resistance of at least 10 minutes for at least one test chemical.
This classification system allows users to make informed decisions about glove selection based on their specific chemical exposure risks.
18 Test Chemicals
One of the most significant updates to EN374-1 is the expansion of the test chemical list from 12 to 18 chemicals. This broader range of chemicals provides a more comprehensive assessment of glove performance against various chemical hazards commonly encountered in different industries.
The 18 test chemicals include:
- 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)
- Ammonium Hydroxide 25% (O)
- Hydrogen Peroxide 30% (P)
- Hydrofluoric Acid 60% (S)
- Formaldehyde 37% (T)
Each chemical is assigned a code letter (A-T) for easy reference in glove markings and documentation [1].
Permeation testing
Permeation testing is a critical aspect of EN374-1, measuring how quickly a chemical moves through the glove material at a molecular level. This test provides valuable information about the breakthrough time, which is the time taken for a chemical to permeate through the glove and come into contact with the skin.
The permeation test is conducted under controlled conditions, typically at room temperature (23°C ±1°C). The test measures the normalized permeation rate, defined as 1μg/min/cm². The maximum duration for the test is 480 minutes, and the results are reported based on the Normalized Breakthrough Time (NBT) achieved.
It’s important to note that factors such as physical stress, higher ambient temperatures, or increased chemical concentrations can shorten the breakthrough time. Additionally, as body temperature is around 37°C, the actual temperature experienced by the glove during use may be higher, potentially impacting its effectiveness.
Chemical resistance pictograms
To simplify the communication of glove performance, EN374-1 introduces new pictograms that quickly inform users about the chemical resistance properties of the gloves. These pictograms appear on certified gloves and their packaging, providing essential information at a glance.
The ‘Chemical resistant’ glove pictogram must be accompanied by at least a three-digit code. This code refers to the code letters (A-T) of at least three chemicals from the list of 18 standard chemicals for which a breakthrough time of at least 30 minutes has been obtained.
For example, a glove marked with “ABC EN 374-1/Type B” indicates that the glove has achieved Type B classification and has been tested against chemicals A (Methanol), B (Acetone), and C (Acetonitrile) with a breakthrough time of at least 30 minutes for each.
These pictograms and codes enable users to quickly identify gloves suitable for their specific chemical handling needs, enhancing workplace safety and compliance with protective equipment standards.
Exploring EN374-2 to EN374-5
EN374-2: Penetration resistance
EN374-2 focuses on determining the resistance of protective gloves to penetration by chemicals and microorganisms. This standard involves two crucial tests to assess the glove’s ability to prevent penetration through imperfections such as tiny holes, cracks, or tears.
The first test is the air leak test, which involves inflating the glove with air pressure and submerging it in a tank of water. Any leaks are identified by visible bubbles. The second test suspends a glove filled with water and examines its outer surface for water droplets.
These tests help ensure that EN 374 gloves provide a reliable barrier against direct paths for chemicals to enter the glove. This is particularly important for older or poorly made gloves, which are more likely to fail due to penetration.
EN374-3 (EN 16523-1): Permeation by chemicals
EN374-3 has been replaced by EN 16523-1, which focuses on determining the resistance of protective glove materials to permeation by chemicals. This test is crucial as it measures how quickly chemicals can break through the glove material at a molecular level, even without any visible or physical changes to the glove.
The permeation test measures breakthrough times, which is the time taken for a hazardous liquid to come in contact with the skin. Each chemical tested is classified in terms of breakthrough time performance levels 0 to 6 [1].
It’s important to note that permeation can occur without any visible signs, making this test a critical component in assessing the effectiveness of chemical-resistant gloves.
EN374-4: Degradation resistance
EN374-4 measures how the glove material reacts when exposed to specific chemicals. This test provides valuable information on what to expect and look for when working with particular chemicals.
Degradation is assessed by observing changes in one or more physical characteristics of the glove caused by chemical contact. These changes may include flaking, swelling, disintegration, embrittlement, color change, dimensional change, hardening, or softening .
It’s crucial to understand that while a glove may show signs of degradation, such as color change, it doesn’t necessarily mean the glove is losing its protective properties. This is where referencing the permeation breakthrough times becomes paramount in assessing the glove’s overall effectiveness.
EN374-5: Protection against microorganisms
EN374-5 specifies the performance requirements for gloves that protect users against microorganisms, including bacteria, fungi, and viruses. This standard has been developed as a separate part of EN374, whereas it was formerly included under EN374-2.
Under EN374-5, gloves are classified into two categories:
- Protection against bacteria and fungi
- Protection against bacteria, fungi, and viruses
All gloves claiming microorganism protection must undergo penetration testing as outlined in EN374-2:2014, which includes air leak and water leak tests. Gloves claiming protection against viruses require additional penetration testing according to ISO 16604:2004, which uses a Phi-X174 bacteriophage to simulate viral penetration.
It’s important to note that gloves longer than 400 mm, or those with cuffs claimed to protect against microorganisms, require additional testing of the cuff area.
The EN374-5 standard uses specific pictograms to indicate the level of protection:
- A shield symbol without “VIRUS” text underneath indicates protection against bacteria and fungi.
- A shield symbol with “VIRUS” text underneath indicates protection against bacteria, fungi, and viruses .
These classifications and pictograms help users quickly identify the appropriate gloves for their specific needs, enhancing workplace safety and compliance with protective equipment standards.
Conclusion
The EN374 standard has a significant influence on workplace safety, providing a comprehensive framework to evaluate protective gloves against chemical and microbiological hazards. By breaking down the standard into its key components – EN374-1 for chemical resistance, EN374-2 for penetration resistance, EN16523-1 for permeation testing, EN374-4 for degradation resistance, and EN374-5 for microorganism protection – this guide offers a thorough understanding of the protective glove standard. This knowledge enables safety professionals and end-users to make informed decisions about hand protection in their workplace.
To wrap up, the recent updates to EN374 have strengthened its effectiveness in addressing evolving safety concerns. The expanded list of test chemicals, new classification system, and updated pictograms provide users with more detailed information about glove performance. As the standard continues to evolve, it’s crucial for users and safety professionals to stay informed about the latest updates and their implications for workplace safety. By understanding EN374 fully, readers are better equipped to ensure proper hand protection and compliance with safety standards in their respective industries.
FAQs
- What distinguishes EN ISO 374-1 Type B gloves from Type C gloves?
- Type B gloves are designed to resist permeation from at least three test chemicals for a minimum of 30 minutes each. On the other hand, Type C gloves provide permeation resistance for at least 10 minutes against at least one test chemical.
- Which type of gloves are suitable for handling 37% formaldehyde?
- Although latex gloves offer limited protection against formaldehyde, it is advisable to use butyl or nitrile gloves for better protection, especially when direct contact with formaldehyde is expected.
- What does the EN 374 standard signify in the context of protective gloves?
- EN 374 is a European standard that categorizes gloves based on their ability to protect against chemicals and microorganisms. Gloves must pass several permeation tests to be certified under EN 374.
- How are glove protection codes interpreted?
- Glove ratings are indicated by a pictogram followed by four numerical performance levels and two letters. The numbers reflect the level of protection, with higher numbers indicating greater protection against mechanical hazards.
References
[1] – https://www.bsigroup.com/globalassets/localfiles/en-gb/product-certification/personal-safety/bsi-technical-guide-glove-standards-changes-en-uk.pdf