4.1.4 Advises on personal eye protection regulations and relevant standards, and appropriately advises patients on their occupational visual requirements.

Question 1

Safety Spex Standards:

MARKINGS ON SPECSAVERS FRAMES:

Answer 1

• Supplier - JCB
• Lens - I2SO (kite marking after the O) (CR39)
• Lens - I1FO (kite marking after the O) (Polycarb)
• Frame - IEN166S CE (kite marking after)
• I = manufacturer marking, 2 or 1 = Optical class, S/F = mechanical impact strength, O = original lens

Question 2

Repairing safety specs?

Answer 2

• Can’t legally repair besides LTB & bending nosepads!
  
  • IF nosepad or screw goes missing, it must be sent back to manufacturer!!! DO NOT repair it in store!! If you do, it will cause its protection capacity to be null and void & will not maintain manufacturer guarantee.

Question 3

JCB Frames:

Answer 3

• The frames are available in metal and polycarbonate, with lens material dependent on the requirements of the specific work activity
  
  • Polycarbonate ordered in for the frame

Question 4

Questions to ask on dispense:

Answer 4

• Tell me about the environment you work in
• What do you do in your occupation?
• Have you worn safety spex before?
• Any high velocity particles coming to you? How big are they?
• Dust, sparks
• Work with chemicals?
• Wear time —> Do you keep your glasses on a lot at work? Do you walk around?
• Face shield, visor etc?

Question 5

Types of Eye Protectors:

Answer 5

• Safety spectacles (side shields)
• Afocal (one-piece wrap around)
• Cup type goggles (RARE)
• Box type goggles
• Face shields
• Helmets

Question 6

Safety Spex:

Answer 6

• Not suitable for dust, gases, molten metal, hot solids, liquid droplets or splashes (BS EN166)
• EN = European normal
• Can be made to fit well
  
  • Can only adjust LTB so must make sure frame fitting well on dispense. If sides broke, replaced by manufacturer
• Able to be glazed with Rx, Has side shields of polycarbonate, Fits well by being more adjustable, Goggles can be worn over, Good ventilation
• Available in plastic frames – safer than metal
• Available in metal frames, disadvantages…
  
  • more damage when impacting on face
  • pads cause injury to nose
  • screws work loose

Question 7

Afocal:

Answer 7

Single piece of polycarbonate, one size & best for emmetropes. Often given by employer!

Question 8

Cup-type Goggles:

Answer 8

• Housing from PVC, good for flying particles, has tint & long bridge
• Poor ventilation & FOV, Uncomfortable

Question 9

Box-type Goggles:

Answer 9

• Good over spectacles, one piece polycarb or cellulose acetate, made of PVC
• Wide FOV, well ventilated
• Not nasally adjustable

Question 10

Face Shields:

Answer 10

Good against splashes, flying particles & viruses

Question 11

MATERIALS:

Answer 11

• Plastic materials
• Polycarbonate

Question 12

MATERIALS:

Plastic Materials:

Answer 12

• Advantages:
  
  • Greater impact resistance
  • Fragments tend to be large and blunt
  • 50% weight c.f. glass
  • Same powers will be thinner than in glass, as no need to thicken for impact resistance
  • Withstands molten metal and hot sparks better, as metal does not fuse with surface so plastic induces less damage
  • Less condensation (lower thermal conductivity - conducts less heat)
  • Greater UV protection than glass
• Disadvantages:
  
  • Soft – easily scratched - worse cosmesis
  • Hardcoat reduces impact resistance

Question 13

Polycarbonate (most commonly used):

Answer 13

• High impact resistance
  Very soft
  Quartz coating often used but can reduce impact resistance from 244m/s to 152m/s
  Good for children’s spex
  Cracks on impact
  No warping or chipping
  Very lightweight
  RI =1.586
  Absorbs UV
  Accompanied by colour fringes in periphery
  Poor V value
  Can be damaged by chemicals more easily such as acetone
• Why can’t an MAR coating be used?
  
  • It reduces impact resistance - problematic due to colour fringes!

Question 14

Frame materials

Answer 14

May be manufactured in metal (often nickel alloys - plated) and plastic (commonly cellulose acetate, polymamide or polycarbonate).

Question 15

Standards & Markings

Standards & Regulations

Answer 15

• Instead of CE marking, may see new UKCA (UK conformity assessed) marking due to UK’s exit from EU
• CE marking will continue to be recognised in GB until 30/06/23

Question 16

Standards & Markings

Markings

Answer 16

• BS EN 166
• CE or UKCA marking
• Manufacturers mark
• Kite mark
• Optical Class
• Mechanical Strength
• Scale number - Code & Shade number
• Fields of Intended Use

Question 17

BS EN 166 and CE or UKCA marking

Answer 17

• BS EN 166 - all protective eyewear in the UK must conform to the European standard EN 166:2002, which has several differing levels of impact resistance, indicated by symbols.
• CE or UKCA marking - Products must meet legal requirements before they can be sold within the European Community, and must carry CE marking. CE marking attached to a product is a manufacturer’s claim that it meets all the requirements of European legislation.

Question 18

Manufacturers mark and kite mark

Answer 18

• Manufacturers mark - various e.g. N = Norville
• Kite mark - is considered the world’s premier symbol of trust, integrity and quality. It indicates that manufacturers carrying the mark have satisfied the most rigorous quality process. The scheme is developed by using BS, EN, ISO or Trade Association specification.

Question 19

• Optical Class

Answer 19

• Optical Class
  
  • This refers to the clarity of the lens, indicating how long and how often the glasses can be safely worn. The relevant number will be marked on the lens. It is divided into three levels:
  • Class 1: Best optical quality (distortion free) and can be worn continuously without harming the eyes.
    Class 2: Lesser optical quality. Suitable for intermittent use.
    Class 3: Lowest optical quality. Suitable for occasional use but should not be worn for any lengthened period of time.
  • 1 = Continuous work
    2 = Intermittent work
    3 = Occasional work

Question 20

• Mechanical Strength

Answer 20

• Mechanical Strength
  
  • S = increased robustness - (toughened glass & thickened CR39)
  • F = low energy impact (polycarbonate & trivex)
  • B = medium energy impact
  • A = high energy impact

Question 21

• Scale number - Code & Shade number

Answer 21

• Scale number - Code & Shade number
  
  • UV filter - numbers are 2 or 3 (BS EN 170)
  • IR filter - numbers are 4,5 or 6 (BS EN 171)
    
    • Sunglare - numbers 5,6 (BS EN 172)
  • Higher shade number = more protective/darker
  • E.g. 2-1.2 (2 is code number, 1.2 is shade number)
  • Welding filters have no code number (BS EN 169)

Question 22

• Fields of Intended Use

Answer 22

Symbol,
3 - liquids (liquid drops/spashes)
4 - Large dust particles (5um>)
5 - Gas and fine dust particles
8 - Short circuit electric arc
9 - molten metals and hot solids

Question 23

Other markings

Answer 23

• 9 - Non-adherence of molten metal and resistance to penetration of hot solids
• K - Resistance to damage by fine particles
• N - Non-fogging properties

Question 24

- Order of Markings:

• OCULARS:

Answer 24

• Scale number (filters only)
  Manufacturer’s mark
  Optical class
  Mechanical strength
  Fields of use
• Scratch resistance
  Resistance to fogging
  Radiant heat (G) (faceshields only)
• CE mark
• Kite mark

Question 25

- Order of Markings:

Frames:

Answer 25

• Manufacturer’s mark e.g. N = Norville
  EN166
  Fields of use (3,4,5,8,9)
  Mechanical strength (F,B,A)
• CE mark
• Kite mark

Question 26

Tests for impact resistance:

Answer 26

S (increased robustness) (5m/s)
F - Low energy impact (12m/s)
B - Medium energy impact (120m/s)
A - High energy impact (190m/s)