According to the EU directive 2000/54EC relating to Biological Substances, employers are obliged to make suitable protective clothing available to their employees. According to EN 14126, in order to protect against bacteria, viruses and other micro-organisms, specific requirements are defined for the clothing materials used to protect against infectious agents. These materials must protect the skin, and therefore the wearer, against possible contact with biological substances and prevent the spread of germs. Suits with sealed seams are recommended, since viruses, bacteria and spores are small enough to penetrate through the openings of sewn seams.

PROTECTIVE CLOTHING TYPES ACCORDING TO EN 14126:2003

Type Description Relevant standard

1aB, 1bB, 1cB, 2B Gas-tight, non-gas-tight EN 943-1
EN 14605 3B Protection against pressurised liquid chemicals
EN 14605 4B Protection against liquid saturation
EN 13034 6B Limited protection against liquid mist or splash
EN ISO 13982-1 5B Protection against airborne solid particulates

EN 14126 COMPRISES THE FOLLOWING MATERIAL TESTS:

Penetration test using synthetic blood (ISO/FDIS 16603)
Resistance to penetration by viruses (ISO/FDIS 16604)
Resistance to penetration by bacteria (ISO/DIS 22610)
Resistance to penetration by biologically contaminated aerosols (ISO/DIS 22611)
Resistance to penetration by contaminated dust (ISO/DIS 22612)

PRELIMINARY TEST ACCORDING TO ISO/FDIS 16603

This is a visual screening test to determine at what test pressure the viral culture test should be conducted. A synthetic blood mixture composed of cellulose, colouring, buffer solution and stabilising agents is used for this test. The pressure at which the liquid penetrates through the material is measured.

VIRAL CULTURE TEST ACCORDING TO ISO/FDIS 16604: USING THE LIMIT DETERMINED IN ISO 16603

The penetration pressure in kPa determined from ISO 16603 is used as the exposure pressure for this test, with a pass, with classification, or fail result.The virus test follows similar protocols to ISO/FDIS 16603, the key difference being that a liquid contaminated with a bacteriophage or virus (Phi-X-174) is used instead of synthetic blood. Any penetration through the test fabric is detected by culturing any contamination on an agar plate.

Classification according to ISO 16604

Class	Exposure pressure [kPa]
6	20.0
5	14.0
4	7.0
3	3.5
2	1.75
1	0.0

BACTERIA TEST ACCORDING TO ISO/DIS 22610:

The standard defines the procedure for testing a material’s resistance to wet bacterial penetration. The test method involves challenging the bacterial-contaminated( Staphylococcus Aureus) donor material of 10 micron HDPE onto the test barrier material, placed on an agar plate and subjecting it to mechanical rubbing. Any penetration through the material is cultured and measured on an agar plate against a control. There are six classes, as defined in the standard, with their corresponding breakthrough times, indicating the point at which the bacteria measurably penetrate the barrier material.

Classification according to ISO/CD 22610 – Resistance to penetration by bacteria

Class	Bacterial penetration [min]
6	> 75
5	> 60
4	> 45
3	> 30
2	> 15
1	< 15

AEROSOL TEST ACCORDING TO ISO/DIS 22611:

The barrier effect of the test material, against biologically contaminated aerosols, is measured using a bacterium solution of Staphylococcus Aureus, which is suspended in an aerosol and sprayed onto both an unprotected cellulose-nitrate membrane and one covered with the test barrier material (the pore size of the membrane is approx. 0.45 μm). The test takes place within a sealed chamber. Both membranes are subsequently analysed to establish their bacterial load by culturing on an agar plate. In order to classify the results, the penetration ratio (ratio of the load of the unprotected cellulose-nitrate membrane to the load of the membrane protected with the test material) is calculated and presented in log units

Classification according to ISO/DIS 22611 – Resistance to penetration by biologically contaminated aerosols

Class	Penetration ratio without/with test material [log]
3	> 5
2	> 2
1	> 1

DUST TEST ACCORDING TO ISO/DIS 22612:

To measure the barrier against contaminated dust, the test materials is pre- sterilised and then fixed into the test apparatus and dosed with contaminated (Bacillus Subtilis) talcum powder. An agar culture plate is located underneath. The test apparatus is agitated or shaken. The particles which penetrate the material are cultured and counted after incubation of the agar plate and a non-contaminated test specimen is run as a control. The results (mean values from 10 single results at a given time) are measured in penetration log units

Classification according to ISO/DIS 22612 – Resistance to contaminated dust (CFU: colony forming units)

Class	Penetration ratio with/without test material [log]
3	≤ 1
2	≤ 2
1	≤ 3

Resistance to Infective Agents EN14126:2003