Table 1 The subset of tests (EN 166) deemed essential to evaluate personal eye protection equipment for COVID-19
Performance requirement | Test method clause | Requirement |
|---|---|---|
General construction (Section 6.1 EN 166:2002) | Visual inspection and manufacturer’s certificates | Eye-protectors shall be free from projections, sharp edges or other defects which are likely to cause discomfort or injury during use. |
Materials (6.2) | Visual inspection and manufacturer’s certificates | No parts of the eye-protector which are in contact with the wearer shall be made of materials which are known to cause any skin irritation. |
Headbands (6.3) | By measuring | Headbands, when used as the principal means of retention, shall be at least 10 mm wide over any portion which may come into contact with the wearer’s head. Headbands shall be adjustable or self-adjusting. |
Field of vision (7.1.1) | The size of the field of vision is defined in conjunction with the appropriate head-form described in clause 17 of EN 168:2001. The test shall be carried out in accordance with clause 18 of EN 168:2001. | Eye-protectors shall exhibit a minimum field of vision defined by the two ellipses when placed and centered at a distance of 25 mm from the surface of the eyes of the appropriate head-form. The horizontal axis shall be parallel to and 0,7 mm below the height of the line connecting the centres of the two eyes. |
The horizontal length of the ellipses shall be of 22.0 mm, the vertical width of the ellipses shall be 20.0 mm. The centre distance of the two ellipses shall be d = c + 6 mm, where c is the pupillary distance. The pupillary distance is 64 mm for the medium head-form and 54 mm for the small head-form, if not specified differently by the manufacture. | ||
Spherical, astigmatic and prismatic refractive powers (7.1.2.1) | The refractive powers of oculars shall be measured by the reference methods specified in clause 6 of EN ISO 18526-1:2020. If, during measurement using the telescope, a doubling or other aberration of the image is observed, then the test sample shall be subjected to further examination using the test method described in 6.3 of EN ISO 18526-1:2020 | The permissible tolerances for oculars without corrective effect are given in the Clause 7.1.2.1.2 of EN166. |
Transmittance – oculars without filtering action (7.1.2.2–1) | Clause 6 of EN ISO 18526-2:2020 | Oculars intended to protect the eyes against mechanical or chemical hazards only, and cover plates, shall have a luminous transmittance greater than 74.4%. |
Diffusion of light (7.1.2.3) | Clause 14 of EN ISO 18526-2:2020 | The max value of the reduced luminance factor shall be 0.50 cd/(m2*lx) for all the other oculars. |
Quality of material and surface (7.1.3) | Clause 6.6 of EN ISO 18526-3:2020 | Except for a marginal area 5 mm wide, oculars shall be free from any significant defects likely to impair vision in use, such as bubbles, scratches, inclusions, dull spots, pitting, mould marks, scouring, grains, pocking, scaling and undulation. |
Minimum robustness (7.1.4.1) | Clause 3.1 of EN 168:2001 | The 7.1.4.1 requires performing an impact test with a 22 mm nominal diameter steel ball, impacting with a force of (100 ± 2) N. |
On so testing the following defects shall not occur: | ||
a) ocular fracture: an ocular shall be considered to have fractured if it cracks through its entire thickness into two or more pieces, or if more than 5 mg of the ocular material becomes detached from the surface away from the one in contact with the ball, or if the ball passes through the ocular; | ||
b) ocular deformation: an ocular shall be considered to have been deformed if a mark appears on the white paper on the opposite side to the one on which the force is applied. | ||
Note: in period of crisis such as the COVID, this should be at least tested using realistic simulations | ||
Resistance to corrosion (7.1.6) | Clause 6.9 of EN ISO 18526-3:2020 | After the test, all metal parts of the eye-protector shall display smooth surfaces, free from corrosion, when they are examined by a trained observer. |
Note: This should be extended to plastic parts considering the sterilization processes and substances (e.g., after cleaning visibility should not be compromised) | ||
Resistance to ignition (7.1.7) | Clause 6.10 of EN ISO 18526-3:2020 | Eye-protectors shall be considered to be satisfactory if no part of the eye-protector ignites or continues to glow after removal of the steel rod. |
Protection against (droplets) and splashes of liquid (7.2.4) | Clause 12 of EN 168:2001 | Face-shields cover the eye-region rectangle of the appropriate head-form as described in 10.2.2.2 of EN 168:2001 as assessed in accordance with 10.2 of EN 168:2001. Additionally, face-shields for protection against splashes of liquids shall have a viewing area with a minimum vertical centre-line depth of 150 mm when mounted in the appropriate housing. |
Lateral protection (7.2.8) | Clause 6.4 of EN ISO 18526-3:2020 | Eye-protectors claimed to provide lateral protection shall pass the lateral region coverage assessment |
Resistance to fogging (7.3.2) | Clause 6.11 of EN ISO 18526-3:2020 | If oculars are described as resistant to fogging they shall remain free from fogging for a minimum of 8 s when tested. |