EN374: Your Ultimate Guide to Chemical and Microbial Protection Gloves

What is EN374?

EN374 is a set of European standards developed by the European Committee for Standardization (CEN) that defines requirements for chemical and microbial protective gloves. Far more than just a checklist, it’s a shield designed to keep hands safe from harmful substances—think acids, solvents, and bacteria—and ensure consistent performance across industries. Whether you’re handling lab chemicals, managing industrial spills, or working in healthcare, EN374 sets the bar for what “protection” really means.

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:

1. 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.
2. 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
3. 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 .
4. 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.

Core Goals of EN374

At its heart, EN374 exists to solve one critical problem: how to stop chemicals and microbes from reaching your skin. Its key objectives include:

• Ensuring gloves act as a reliable barrier against liquids, gases, and microorganisms.
• Giving users clear, standardized info to pick the right glove for the job (no more guesswork).
• Holding manufacturers accountable for quality, so every glove that meets EN374 works as promised.

The 5 Parts of EN374: Breaking It Down

EN374 isn’t a single rule—it’s a team of standards, each tackling a specific part of protection. Here’s what each part does:

1. EN374-1: Terms and Test Methods

Think of this as the glossary and instruction manual. It defines key words (like “penetration” vs. “degradation”) and lays out how to test gloves. For example:

• Penetration test: Measures how long it takes a chemical to seep through the glove material (recorded as “breakthrough time”). A longer time means better protection.
• Degradation test: Checks if the glove swells, cracks, or weakens after 30 minutes of contact with a chemical. Changes in weight, thickness, or tensile strength indicate degradation.

New classification system

• Type A: Highest level of protection, permeable to at least 6 types of test chemical substances for a minimum of 30 minutes.
• Type B: Provides a moderate level of protection. Type B gloves offer a permeation resistance of at least 30 minutes against no fewer than three types of test chemicals.
• Type C: Basic level of protection, with a permeation resistance of at least 10 minutes against no fewer than one type of test chemical.

This classification system enables users to make informed decisions when selecting gloves based on their specific chemical exposure risks.

New Markings

These pictograms and codes enable users to quickly identify gloves that are suitable for their specific chemical handling needs, thereby enhancing workplace safety and meeting protective equipment standards.

18 chemical substances

Each chemical is assigned a code letter (A-T) for quick reference in glove markings and documentation.

1. Methanol (A)
2. Acetone (B)
3. Acetonitrile (C)
4. Dichloromethane (D)
5. Carbon Disulphide (E)
6. Toluene (F)
7. Diethylamine (G)
8. Tetrahydrofuran (H)
9. Ethyl Acetate (I)
10. n-Heptane (J)
11. Sodium Hydroxide 40% (K)
12. Sulphuric Acid 96% (L)
13. Nitric Acid 65% (M)
14. Acetic Acid 99% (N)
15. Ammonium Hydroxide 25% (O)
16. Hydrogen Peroxide 30% (P)
17. Hydrofluoric Acid 60% (S)
18. Formaldehyde 37% (T)

2. EN374-2: Performance Requirements

This is where the rubber meets the road. It spells out the must-have features for a glove to earn the EN374 stamp:

• Passing penetration tests for at least 3 common chemicals (e.g., sulfuric acid, sodium hydroxide).
• Meeting basic physical standards (tensile strength, tear resistance) so gloves don’t fall apart mid-use.

3. EN374-3: Microbial Protection

Microbes (bacteria, viruses) are tiny but dangerous. This part ensures gloves block them too, with tests that mimic real-world scenarios—like handling contaminated fluids in hospitals or labs.

4. EN374-4: List of Test Chemicals

Ever wondered which chemicals gloves are tested against? This part lists them all, from strong acids (“A” category) to solvents (“C” category). It’s like a cheat sheet for choosing gloves for specific tasks.

5. EN374-5: Microbial Protection Add-ons

A deeper dive into keeping microbes out, with extra rules for high-risk settings (e.g., pandemic response, biohazard labs). It clarifies how to prove a glove stops even the trickiest viruses.

Detailed Testing Methods in EN374

The rigor of EN374 lies in its precise testing protocols. Here’s how gloves are put to the test:

1. Chemical Penetration Testing (EN374-1)

This test measures how long a glove can resist a specific chemical before it seeps through (called “breakthrough time”).

• Process: A glove sample is stretched over a two-chambered device. One chamber is filled with the test chemical (e.g., 30% sulfuric acid, acetone), and the other with a detector (e.g., a sensor or absorbent material).
• Pass Criteria: For a glove to be certified for a chemical, the breakthrough time must exceed a minimum threshold (e.g., ≥30 minutes for most industrial chemicals). The longer the time, the higher the protection level.
• Why It Matters: Prevents “invisible” exposure—even small amounts of a chemical seeping through can cause burns or toxicity.

2. Degradation Testing (EN374-1)

Chemicals can weaken glove materials over time. This test checks if a glove holds up after contact.

• Process: Glove samples are immersed in a chemical for 30 minutes, then dried. Testers measure changes in:
  • Weight: Swelling (gain) or shrinking (loss) indicates the chemical is breaking down the material.
  • Thickness: Hardening (thicker) or softening (thinner) signals structural damage.
  • Tensile Strength: A drop in the force needed to tear the glove means it’s become brittle or weak.
• Pass Criteria: Changes must stay within strict limits (e.g., weight gain ≤15% for nitrile gloves exposed to oils).

3. Microbial Barrier Testing (EN374-3 & EN374-5)

To stop bacteria and viruses, gloves must act as an impenetrable shield.

• Process:
  • For bacteria: A glove is stretched over a container filled with a high-concentration bacterial solution (e.g., Staphylococcus aureus). The outer surface is swabbed after 1 hour to check for leakage.
  • For viruses: A similar setup uses virus suspensions (e.g., phi-X174, a surrogate for human viruses). Viral particles are counted on the outer surface using PCR or cell culture.
• Pass Criteria: No detectable microbes on the outer surface—even a single colony or viral particle is a failure.

4. Physical Durability Testing (EN374-2)

A glove that tears easily is useless, even if it resists chemicals.

• Tensile Strength: Measures the force needed to stretch a glove until it breaks. EN374 requires a minimum of 10 MPa (megapascals) for most materials—strong enough to withstand rough handling.
• Tear Resistance: Tests how much force is needed to rip a pre-cut sample. Gloves must resist at least 15 N (newtons) to avoid tearing during use.

Comparison with Related Standards

What EN374 Means for You

• Workers: Look for the EN374 label to know your gloves are tested against the chemicals/microbes you face. The packaging will even tell you how long (e.g., “≥30 minutes” protection against solvent X).
• Employers: It’s your assurance that you’re providing gear that actually works—no cutting corners on safety.
• Manufacturers: A clear roadmap to build gloves that meet EU standards and gain global trust.

EN374 isn’t the only player in protective glove standards. Here’s how it stacks up:

Key Myths Busted

• Myth: EN374 gloves are only for chemists.Fact: They’re used in healthcare (to block germs), cleaning (to resist bleach), and even tattooing (to prevent cross-contamination).
• Myth: All EN374 gloves protect against everything.Fact: Gloves are tested against specific chemicals—check the label for which ones! A glove great for acids might fail with solvents.

EN374 isn’t just about compliance—it’s about confidence. When you see that label, you know someone’s already done the hard work of making sure your gloves have your back.