A Comprehensive Guide on EN420 For Gloves & Why Is It Changed To EN ISO 21420

When it comes to personal protective equipment, gloves are the most often used due to their relevance in many sectors. Whether you’re working with microbiological samples in the lab, chemicals in the industrial or pharmaceutical fields, or thermal or mechanical items, you’ll need gloves that provide strong protection against all types of hazardous materials, and hence high safety standards.  

Consequently, certain safety standards have been formulated called “EN420“, which is known to be the European PPE glove criteria.

These standards should be followed by glove companies in order to provide high levels of protection before following any additional standards.

Since 2003, practically all gloves have been manufactured in accordance with the standard specifications. The international standard organization (ISO), however, made certain changes and replaced EN 420 with EN ISO 21420. 

In this article, I will go through the EN 420 standard in further details, as well as all of the changes that have been made by the ISO and how things currently operate. Just keep reading.

New: Standard EN 420: 2020 

Scope:

It has been stated by the international standard organization for the general requirements and test methods for the ISO 21420:2020 that “the document specifies the general requirements and relevant test procedures for glove design and construction, innocuousness, comfort and efficiency, as well as the marking and information supplied by the manufacturer, applicable to all protective gloves.

It can also apply to arm protectors and gloves permanently incorporated in containment enclosures.” 

Moreover, “Gloves and hand protectors such as mittens, pot holders and arm protection are covered by this document. This document does not address the protective properties of gloves and therefore is not used alone but only in combination with the appropriate specific standard(s). A non-exhaustive list of these standards is given in the Bibliography.”

So, let us discuss each of the general requirements and test methods:

Chemical innocuousness

Chemical innocuousness is one of the main criteria for EN420, which merely defines the materials used in the fabrication of gloves.

For example, the glove’s material should not emit any substance known to be toxic, likely to cause cancer, inducing mutations, or even be allergic or corrosive (1). 

Therefore, a list of tests has been used in EN420:2003 and a group of additional ones are listed for EN420:2020 as follows.;

  • Nickel release

The total amount of metallic compounds in contact with the skin should be less than 0.5g/cm2/week.

  • Azo colorants 

Carcinogenic aromatic amines are present in all textiles and leather-based products, and they should be limited to less than 30 mg/kg.

  • pH value

The determination of pH value (EN 420, 4.3.2) indicates how acidic or alkaline it is, using a pH scale ranging from one to fourteen.

Skin irritations can develop if a substance in a PPE product has an extremely high or extremely low pH value, and especially if the acids or alkalis present are “strong”.

The pH value of all materials other than leather is analyzed quantitatively should be with a reference range value of less than 9.5 and larger than 3.5.

Moreover, it is well known that the pH value for each item is given separately in case the glove has multiple layers.

  • Chromium VI

Small levels of chromium III can be oxidized to chromium VI during the tanning process or under certain storage circumstances, which is a recognized as carcinogenic. Therefore, Chemical innocuousness testing of leather-based products evaluated should be less than 3 part per million (PPM) as a maximum detectable limit. 

  • polycyclic aromatic hydrocarbons (PAHs)

Rubber and plastic products that come into contact with the skin and are being tested should have less than 1 mg/kg of each of the eight banned PAHs.

  • Dimethylformamide (DMFa)

All of the products being evaluated for compatibility with polyurethane coatings should have less than 1000 mg/kg.

 

More information about chemical innocuousness:

Aside from the compounds expressly stated in the standard, notified entities may additionally need proof of conformity with restricted substances laws, such as REACH (Regulation (EC) No. 1907/2006) Annex XVII.

The restricted fungicide pentachlorophenol (PCP) is mentioned in Annex XVII entry 22 and is relevant to leather and natural fabrics. The need is less than 1,000 mg/kg (less than 5 mg/kg in Germany).

Furthermore, item 51 limits the presence of four phthalate plasticizers in goods to less than 0.1% by mass of the plasticized substance.

The plasticizers are added to improve the softness and flexibility of the polymer, which is especially important for vinyl gloves. The four plasticizers are as follows: Bis (2-ethylhexyl) phthalate (DHEP), dibutyl phthalate (DBP), benyl butyl phthalate (BBP), and diisobutyl phthalate (DIBP).

What is the difference between the old and new standard regarding chemical innocuousness?

The new standard includes additional chemical limitations, such as a restriction on DMFa (Dimethylformamide) concentration of no more than 1000 mg/kg (2).

Aromatic Polycyclic Hydrocarbons (PAHs) content in rubber or plastic products, on the other hand, is limited to 1 mg/kg.

  • Minimal gloves dimensions’ requirement 

The minimal glove dimension restrictions have been omitted from the new standard.

However, some types of gloves that need special criteria, such as firefighting gloves, were exempted.

Furthermore, various size methods may be used if they are defined in terms of EN ISO 21420:2020.

This information should be included on the user information leaflet that comes with the protective gloves.

  • Hand sizing scheme 

The new standard makes no modifications to the hand sizing scheme. Furthermore, the new guidelines permit you to use your own hand sizing system.

In this scenario, the user guidelines should include measurements of hand length (the distance from the wrist to the tip of the middle finger) and hand circumference.

 

Glove size  Fits hand size  Hand circumference/ length (mm)  Minimum length of the glove (mm)
6 6 152/160 220
7 7 178/171 230
8 8 203/182 240
9 9 229/192 250
10 10 254/204 260
11 11 279/215 270

Electrostatic properties 

A protective glove is recommended to be used in some workplaces that are known to be high-risk due to the presence of flammable or explosive substances (3).

The electromagnetic properties of these gloves are intended to be tested according to the test method EN 16350. 

A pictogram (Pictogram 2415 of ISO 7000) shall be used as a marker for protective gloves that have been tested and meet the requirements of EN 16350.

Furthermore, user instructions and test conditions should be included in the manufacturer’s documentation.

What is the difference between the old and new standard regarding the electrostatic properties?

The main difference between the standards is that the electrostatic properties of protective gloves according to EN420:2003 must be examined using test method EN1149.

Furthermore, there is no pictogram for these gloves.

  • Dexterity

Glove dexterity should be evaluated based on the elasticity, thickness, and deformability of the glove.

The diameter of the smallest steel pin that can be picked up three times in 30 seconds is used to calculate dexterity.

The level obtained is 0 if no pins can be picked up. Finger dexterity can be tested for a specific usage if necessary.

Below you can find references for dexterity and its level of performance:

Levels of performance Smallest Diameter
1 11
2 9.5
3 8
4 6.5
5 5

 

What is the difference between the old and new standard regarding the glove dexterity?

     Within the new standard, no new modifications have been developed.

Water transmission and absorption 

According to the water vapor transmission and absorption standard (EN 420, 5.3), protective gloves should enable water vapor transmission to promote comfort by enabling perspiration to exit the glove, hence assisting user comfort.

How water transmission and absorption being evaluated?

In case of rubber or polymeric gloves will not transmit water, therefore the test is irrelevant here. 

How about the other types of gloves?

According to the journal for employee protection, it has been stated that other types of gloves are tested for water vapor transfer by clamping a sample of material in the mouth of a container containing a solid desiccant and keeping it in a conditioned environment in a fast current of air.

By moving the desiccant, the air within the container is circulated. The desiccant absorbs moisture from the air that has passed through the material, causing the container to increase weight.

The data are given in milligrams per second (cm 2 .h). The specification specifies that the materials must have a water vapor transmission of at least 5mg/m2 if needed (cm 2 .h).

Moreover, when the glove design and material hinder water vapor transport, the glove should be absorbent to lessen the impacts of perspiration.

A sample of material is clamped over the mouth of a sealed container over a reservoir of water to evaluate this attribute. Water vapor is absorbed from the air within the container throughout the test and is expressed in mg/cm 2.

According to EN 420, the glove must have a water vapor absorption of at least 8mg/cm 2 when tested for eight hours.

Marking 

The new standard considers the label on each protective glove to be a mandatory requirement.

Because performance levels are altered by ageing, the label should mention both the manufacture date and the expiry date of the glove.

What is the difference between the old and new standard regarding the marking?

In accordance with the former standard (EN 21420), the labelling for each glove typically contains the manufacturer’s name, the CE mark, the glove identification, and unique pictograms that represent the performance level.

Extractable protein content

One of the most common medical examination gloves is the “latex glove,” which is simply made of natural latex proteins.

The material is known to cause allergies in some cases for the patient who comes into close contact with the glove as well as the physician.

Therefore, the determination of the extractable protein content of these latex products is recommended by EN 420:2003 (old standard) (4).

What is the difference between the old and new standard regarding the Extractable protein content?

Detecting the presence of extractable proteins in natural rubber latex gloves is no longer a required test in the new standard.

However, it should be mentioned that the gloves contain latex that may induce allergy.

Water penetration 

Another optional test was added for testing the resistance of the glove material to water penetration. 

According to the journal for employee protection, it has been stated that for leather gloves a sample of the leather is subjected to penetrometer test where it is clamped to circular clamps and flexed in a trough of water.

The leather is flexed until water penetrates from the outer side of the leather to the inner side and is recorded as the number of minutes to penetration. Four levels of performance are defined within EN 420, ranging from Level 1, (which is equivalent to penetration occurring between 30 and 60 minutes) to Level 4, where penetration does not occur before 180 minutes.

An alternative more applicable test is used to assess textile materials.

This method uses hydrostatic head equipment, which applies a column of water at steadily increasing pressure to the outer surface of the gloving material until penetration of water through to the inner surface occurs.

The results for this test are recorded as the pressure required to cause penetration and is recorded in Pascals.

EN 420 does not contain a requirement for this test, but does require that the level of resistance is communicated to the customer. There is unfortunately no correlation between the results obtained through these different test methods.

What is the difference between the old and new standard regarding the water penetration test?

The new standard does not include the water penetration test and as mentioned, it was an optional choice in the old standard.

And now…

You must be thinking about the status of EN 420:2003? Is it valid?

The good news is the old EU certifications acquired in accordance with the old EN 420 standard are still valid.

Final words

I hope you found all the information you needed to know about the old and new standards of EN420 and enjoyed reading it.

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