Comprehensive Occupational Dispensing and Safety Spectacles Guide

Context and Risk Management in Occupational Dispensing

  • Environment and Settings: Patients requiring safety spectacles typically work in environments necessitating eye and potentially other forms of protection (e.g., ear, head, or respiratory protection).

  • Employer Responsibilities:

    • Large employers typically have risk management operations in place.

    • Employers usually negotiate supply contracts directly with prescription houses or manufacturers.

  • Small Businesses and Individuals: Extra consideration is required for self-employed individuals and small businesses that may lack in-house specialist expertise in health and safety.

  • Amateur/Hobbyist Activity: Professionals must also consider the "amateur" who performs hazardous activities as a hobby and may require similar levels of protection.

Procedure for Providing Safety Spectacles

  • Order Intake: The patient (employee) usually attends the practice with a requisition or order form.

  • Predetermined Specifications: Information such as lens type, material, grade of protection, and frame style may already be pre-selected on the order form by the employer/prescription house.

  • Optometrist’s Professional Responsibility:

    • Despite pre-filled forms, the optometrist retains a duty of care to confirm the suitability of the appliance for the patient's specific needs.

    • If the optometrist is not satisfied with the prescribed protection or specifications, they must contact the employer or safety officer.

  • Workflow:

    • The optometrist completes the prescription and specific lens details.

    • The optometrist or Dispensing Optician fits the completed spectacles upon arrival.

  • Financial Structure:

    • The prescription house pays a dispensing fee to the optometrist.

    • The employer pays the prescription house directly for the appliance.

Visual Task Analysis (VTA)

A thorough Visual Task Analysis is essential for safety dispensing. The following data points must be documented:

  • Hazard Identification:

    • Flying metal particles.

    • Chemicals/Solvents.

    • Dust.

    • Other (specified by the clinician).

  • Distance Requirements:

    • Distance, Intermediate, and Near tasks must be identified.

    • Required working distances must be measured and recorded for each.

  • Spatial Characteristics:

    • The direction of gaze (e.g., tasks positioned above eye level).

    • The width of the work area.

    • Whether the tools or equipment involved are moving or stationary.

  • Assessment of Current Eyewear:

    • Current lens types: Single Vision (SV), Degressive, Bifocal, Trifocal, or Varifocal (PAL).

    • Current prescription (RxRx).

    • Material and Optical Centers (OCsOCs).

Hazard Assessment and Patient Discussion

  • Occupational Detail: The generic job title (e.g., "engineer") may not be instructive enough. Optometrists must elicit detailed information regarding specific daily tasks.

  • Chemical Hazards: Assess the nature of the chemical to determine if the risk is limited to the eyes or the entire face, and if the substance will degrade the lens material.

  • Dust Hazards: Assess the type of dust to determine if it is abrasive or if ventilation in the frame is required.

  • Presbyopic Considerations: Detailed analysis of Distance (D), Intermediate (I), and Near (N) tasks is significantly more critical for presbyopic patients to ensure functional vision across all working ranges.

Evaluation of Existing Spectacles

  • General and Protective Wear: Practitioners should obtain details for both the patient's everyday spectacles and any existing protective eyewear.

  • Functional Assessment: Identify what aspects of the current eyewear are successful and what are failing.

  • Additional Protection: Determine if the patient uses supplementary protection (e.g., over-goggles or shields) that will be worn simultaneously with the new spectacles. It is recommended that they bring these items to the fitting to ensure compatibility.

Occupational Lens Options and Strategy

  • Lens Selection: Depending on the task analysis, patients may require SV, bifocals, trifocals, PALs (Progressive Addition Lenses), or degressive lenses.

  • Specialized Designs:

    • Double D: Specialized bifocals with segments at the top and bottom of the lens to accommodate tasks above head height.

  • Constant Protection Strategy: The goal is to ensure the worker is protected at all times.

    • For emmetropic presbyopes, a bifocal or PAL may be preferable over single-vision reading lenses to prevent the patient from removing the spectacles when switching tasks.

    • A single pair of spectacles that covers all distances is ideal for safety compliance.

  • Limitations of PALs and Degressives:

    • Cost: Employers often limit PAL selections to 1 or 2 "basic" designs to manage expenses.

    • Degressives: These may be limited by blurred distance vision, which may lead to the patient changing spectacles and leaving their eyes unprotected during the transition.

Frame Selection and Materials

  • Style Constraints: Safety frames often have limited cosmetic appeal and a restricted range of styles. Practitioners must manage expectations regarding current fashion.

  • The "Home" Risk: Patients may be tempted to wear safety frames at home or remove side shields for aesthetic reasons. This must be discouraged as it compromises the protective function.

  • Necessary Dispensing: Do not dispense features or appliances that are not clinically or Occupationally necessary.

  • Legal Duty: The employee has a legal duty to maintain and wear the appliance. Any unauthorized alterations (e.g., removing side shields) will invalidate the insurance.

  • Metal vs. Plastics:

    • Disadvantages of Metal Frames:

      • Rim screws can loosen over time, making lenses insecure.

      • Glazing is more critical; small lenses can be pushed out on impact, while oversized glass lenses under stress may suffer spontaneous breakage.

      • Narrower rims provide less protection from the edge of the lens being pushed back into the face.

    • Style Advantage: Metal frames may offer materials/styles that are slower to go out of fashion and can sometimes serve as unisex designs.

Fitting and Side Shield Design

  • Orbital Protection: The frame should be fitted so the top rim sits slightly higher than normal to protect the orbit. In the event of a heavy impact, the frame should hit the bony structure of the face rather than the eyeball.

  • Adjustability:

    • Check for reversible adjustments, such as the pantoscopic angle and crest height.

    • Ensure side shields do not obstruct the required adjustments.

  • Side Shield Evaluation:

    • Are the shields removable?

    • Are there gaps between the shield and the face?

    • Can the angle of the side (let-back) be adjusted with the shields in place?

Fitting Checklist for Safety Eyewear

A critical fit is essential for safety. Practitioners must ensure:

  1. Pressure: No uncomfortable pressure points on the sides of the head or behind the ears.

  2. Stability: The nose piece sits on the nose without pinching or sliding.

  3. Field of View: Peripheral vision should not be obstructed.

  4. Coverage: The lens must cover the eyebrow, eye socket, and all surrounding soft tissue.

  5. Weight: The weight should be evenly distributed.

  6. Proximity: The eyewear should fit close to the face without touching the eyelashes. There should be no gaps along the top, bottom, or sides.

  7. Movement: The eyewear must remain comfortable and in place when the head moves forward/backwards or tilts side to side.

Ordering and Measurements

  • Complete Appliance Units: Optometrists cannot send empty frames to be glazed or reglaze existing frames. The prescription house must certify and mark the entire appliance (both frame and lenses) as a single unit.

  • Ordering Constraints: Adjustments are more limited than conventional frames. The area around the lug/joint may be inaccessible due to side shields.

  • Required Measurements:

    • Eyesize and Distance Between Lenses (DBLDBL).

    • Side length to bend (LTB). Note: Ensure LTB is measured, not FTB (Front to Bend).

    • Angle of side.

    • Headwidth measurement.

  • Headwidth Formula:     Headwidth Ordered=Measured Headwidth−10 mm\text{Headwidth Ordered} = \text{Measured Headwidth} - 10\,\text{mm}

Marking and Identification

  • Certification Marks: The clinician must check for specific markings on both the lenses and the frames.

  • Lens Markings:

    • Manufacturer’s mark.

    • Certification symbol (e.g., € or C).

  • Frame Markings:

    • Manufacturer's identification.

    • Certification symbol.

  • Note: It is usually not possible for standard spectacles to cover high levels of impact resistance or specific hazardous gases.

Limitations of Safety Spectacles

  • Inadequate Protection: Most severe hazards cannot be managed with spectacles alone.

    • Gases/Liquids: Require sealed goggles.

    • Molten Metals: Require a full-face shield.

  • Prescription Inserts: Some goggles allow for a prescription insert. Note that the insert itself does not necessarily need to be impact-resistant, as the outer goggle provides the protection.

  • Combination PPE: If extra protection is needed, the patient may need a plano goggle/shield to wear over their spectacles.

    • Practitioners must ensure compatibility with other devices like ear defenders.

    • Patients must be warned about the specific limitations of the protection provided.

  • Patient Education: Upon collection, the patient must be reminded of their legal responsibilities regarding the maintenance and use of the safety appliance.