La. Admin. Code tit. 55 § III-1123

Current through Register Vol. 50, No. 9, September 20, 2024

Section III-1123 - Optical Properties of Eye Protection Devices

A. Lenses of EPD's shall comply with the following requirements.

1. Lenses shall be made of material suitable for ophthalmic use, and shall be free from striae, waves, bubbles, or any other defects which may impair their optical quality.

2. The prismatic effect of a non-corrective lens shall not exceed 1/8 diopter at any point within the specified minimum field of vision. In the case of eye glasses, each non-corrective lens shall comply with the limitation of prismatic effect.

3. In any meridian, the refractive power of a non-corrective lens shall not exceed plus or minus 1/3 diopter and the difference between the refractive powers in any two meridians shall not exceed 1/8 diopter.

4. The definition afforded by a non-corrective lens shall be such that a line pattern with lines separated not more than 24 seconds of angle shall be clearly distinguishable when viewed through the lens.

B. The compliance of a lens with the prismatic effects, refractive power, and definition requirements §1123. A.2 herein above, shall be determined in accordance with those tests methods described in the American National Standards Institute Standard Z87.1-1989. In order to maintain consistency in the results of tests conducted by various organizations, the following test requirements must be met.

1. An 8-power telescope with focusing arrangement to accommodate the refractive effects of both positive (converging) and negative (diverging) lenses placed between the telescope and test chart shall be used. The illuminated target and test chart shall be a central dot and a concentric circle one inch in diameter plus one of the high contrast (black and white) NBS resolution Test Charts dated 1952 and printed on lens resolution charts to accompany NBS Circular 374. The chart shall be perpendicularly aligned 35 feet from the objective lens of the telescope when the telescope is properly focused with no test, sample, or other lens between the objective lens and the chart. The center dot and the periphery of the concentric circle 1 inch in diameter shall be used when testing for prismatic effect. The test pattern marked "20" shall be used when testing for refractive power and when testing for definition. Standard lenses of plus or minus 1/8 diopter shall be used when testing for refractive power.

2. Other standard methods of testing that are equivalent or superior, as regards to accuracy, quality and consistency of results, to the above specified National Bureau of Standards methods, may be used to determine compliance only when such methods are approved by the Deputy Secretary, Department of Public Safety and Corrections, Public Safety Services.

C. Minimum Horizontal Field of Vision. Except as provided in §1123. C.1 below, each EPD shall not obstruct a horizontal field of vision to at least 105 degrees to the right side of the sagital plane that passes through the pupil of the right eye, and at least 105 degrees to the left side of the sagital plane that passes the pupil of the left eye.

1. The specified minimum horizontal field of vision shall be unobstructed except that the horizontal field provided by spectacles or sunglasses may be obstructed by the frame in a sector no greater than 7 1/2 degrees in horizontal angular width and located between 50 degrees and 80 degrees of the pertinent sagital plane passing through the eye pupil.

2. When ascertaining the horizontal filed of vision afforded by eye glasses, the pupil of the eye shall be assumed to be located 17 millimeters behind the point on the rear surface of the lens where the horizontal and vertical diameters intersect. When ascertaining the horizontal field of vision of EPD's other than eye glasses, the assumed location of the pupil of the eye relative to the structures of the EPD shall be that location which is most likely to occur when the EPD is attached and worn in accordance with the manufacturer's instructions.

3. No portion of the minimum horizontal field of vision shall be obstructed by a temple piece, headband, helmet, helmet attaching device, or any other supporting attaching device.

La. Admin. Code tit. 55, § III-1123

Promulgated by the Department of Public Safety and Corrections, Office of State Police, LR 27:66 (January 2001).

AUTHORITY NOTE: Promulgated in accordance with R.S. 32:190.