Association of British Dispensing Opticians

Protective eyewearA reference guide for ABDO members

New 2014revised edition

Industrial prescription protective eyewear

Legal requirements

On 1st January 1993, in line with aEuropean Directive, the Government ofthe UK introduced new legislation onHealth and Safety at Work. Theseeffectively replaced the old UK legislationof 10th April 1947.

Six areas were considered within thelegislation, one of which was personalprotective equipment (PPE). Theregulations were published under theHealth and Safety at Work Act 1974 asPersonal Protective Equipment (EuropeanCommunity EC Directive) Regulations1992 SI 1992/3139.

Eye protection was included in theseregulations.

The 1993 regulations apply to all workersin the UK, with the exception for crewsof sea-going ships (there is also somedebate about the protection affordedto military personnel).

As a result of the publication of these rulesall previous legislation was completelyrevoked. The regulations relating to eyeprotection are now taken as EuropeanNormals ie EN standards.

British, European and Internationalstandards are:

• BS EN 169:1992. Personal eye protection:Filters for welding and relatedtechniques: Transmittance requirementsand recommended use

• BS EN 172:1995. Specification forsunglare filters used in personal eyeprotectors for industrial use

• BS 7930-1:1998. Eye protectors forracket sports. Squash Oculars.

• BS EN 174:2001. Ski goggles fordownhill skiing.

• BS EN 166:2002. Personal eye protection:Specifications

• BS EN 167:2002. Personal eye protection:Optical test methods

• BS EN 168:2002. Personal eye protection:Non optical test methods

• BS EN 170:2002. Personal eye protection:Ultraviolet filters: Transmittancerequirements and recommended use

• BS EN 171:2002. Personal eye protection:Infrared filters: Transmittancerequirements and recommended use

• BS EN 379:2003 + A1: 2009. Personaleye protection. Automatic weldingfilters. Welding filters with transmittancevariable by time and zone

• BS EN 14458:2004. Personal eye-equipment. Faceshields and visorsfor use with firefighters' and highperformance industrial safety helmetsused by firefighters, ambulance andemergency services.

• BS EN 1731:2006. Personal eyeprotection. Mesh eye and faceprotectors

• BS EN ISO 4007:2012. Personalprotective equipment - Eye and faceprotection - Vocabulary

• BS EN ISO 8980-3:2013 Ophthalmicoptics - Uncut finished spectacle lensesPart 3: Transmittance specifications andtest methods

• BS EN ISO 12312-1:2013 Eye and faceprotection - Sunglasses and relatedeyewear - Part 1: Sunglasses forgeneral use

• BS EN ISO 12311-1:2013 Personalprotective equipment - test methods forsunglasses and related eyewear

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Spectacles, goggles and shieldsAs previously stated, all protectiveeyewear in the UK must conform to theEuropean standard EN 166:2002, whichhas several differing levels of impactresistance, indicated by symbols.

The range of symbols used in lens typemarking are:

Symbol Property

S Increased robustness(toughened glass andthickened CR39)

F Low energy impact(polycarbonate and Trivex)

B Medium energy impact

A High energy impact

9 Non-adherence of moltenmetal and resistance topenetration of hot solids

K Resistance to damage byfine particles

N Non-fogging properties

Note: When medium energy impactresistance, denoted as EN 166 B, isrequired or, there is a requirement forprotection against electrical arcs,welding materials and corrosive materials,prescription spectacles should not besupplied and goggles, or visors, should beconsidered, which must carry theappropriate EN specifications.Grade B test: 6mm, 0.86g steel balltravelling at 120 metres per second

When high energy impact resistance(EN 166 A) is required visors or faceshields must be supplied. Grade A test: 6mm 0.86g steel balltravelling at 190 metres per second

Low energy impact grade (EN 166 F ) isthe highest level of impact offered byprotective spectacles/glasses. Grade F test: 6mm, 0.86g steel balltravelling at 45 metres per second(polycarbonate and Trivex)

CR39 (with increased thickness) andtoughened glass (usually thermallytoughened in the UK) are materialsoffering increased robustness (EN 166 S). Grade S test: 22mm, 43g steel balltravelling at 5.1 metres per second. This isderived from the practical test which is todrop the ball (as stipulated) from a heightof 1.3 metres.

Types of protective eyewear

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Markings required on the lenses ofsupplied protective spectacles

N ..................... Manufacturer’s mark 1...................... Optical class S or F .............. Impact grade

There will probably also be a Kitemark,which is not a regulatory requirement, buta manufacturer’s stamp of quality.

The Kitemark: is considered the world'spremier symbol of trust, integrity andquality. It indicates that manufacturerscarrying the mark have satisfied the mostrigorous quality process. The scheme isdeveloped by using BS, EN, ISO or TradeAssociation specification.

LensesMarks: The manufacturer’s mark, whichis useful as the source is traceable in theevent problems, (plus Kitemark), 1 - F or1- S.

In a number of working environments itmay well be possible to only provideappropriate over-goggles, or side shields,to spectacle wearers, but such stepsshould only be regarded as temporarymeasures. It should be noted that thesemeasures are not suitable for prolongedor regular use.

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

Functionality and use dictates theirdesign, but a range of colours and stylesare readily available from theappropriate suppliers.

Frames must also carry the appropriatemarkings, which are:

Marks: Manufacturer’s mark, offeringtraceability (plus Kitemark, not arequirement).

EN 166........... Relevant standard.F..................... If the frame claims to meet

low energy impact (nomarkings are required forGrade S increasedrobustness).

CE mark ....... Products must meet legalrequirements before theycan be sold within theEuropean Community, andmust carry CE marking. CEmarking attached to aproduct is a manufacturer'sclaim that it meets all therequirements of Europeanlegislation.

BS EN 166 PROTECTOR TYPEFrames Lenses Spectacles Goggles Faceshields

Manufacturer’s mark R R • • •

Optical class

Refractive power +/-0.06 - 1 • • •

Refractive power +/-0.12 - 2 • • •

Refractive power +0.12 - 3 • •

Refractive power - 0.25 - 3 • •

Mechanical strength

Increased robustness - S • • •

Low energy impact -F F • • •

Medium energy impact -B B • •

High energy impact -A A •

Field of use

Liquid droplets/Splashes 3 - • •

Large dust particles 4 - •

Gas/Fine dust particles 5 - •

Short circuit electric arc 8 - •

Molten metal/Hot solids 9 9 • •

Resistance to fogging - N • • •

Resistance to surface - K • • •damage (damage by fine particles)

Technical information

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ReferenceNorville Group. Protective Eyewear. Catalogue dated February 2012 p11.

General

BS EN 166:2002 - Personal eye protection -specificationsNot all types of eye protector arepermitted to meet all these requirements.

The order of markings on oculars, whererelevant, is:• Scale number (filters only)• Manufacturer’s mark• Optical class• Mechanical strength• Fields of use• Scratch resistance• Resistance to fogging• Radiant heat

The order of markings on frames, whererelevant, is:• Manufacturer’s mark• EN166• Fields of use• Mechanical strength

Scale number - for oculars with filteringeffect only. Higher numbers have astronger filtering effect (eg are darkerfor welding). Scale number consists ofa code number and a shade numberseparated by a hyphen, except forwelding filters which have no codenumber. For example, an IR filter withshade number 4 has the scalenumber 4-4.

Welding filters - see BS EN 169 andBS EN 379Shade number between 1.2 and 16.Suffix a denotes filter for use in gaswelding with flux.

UV filters - see BS EN 170 2- or 3- minus code number denotingUV filter without or with good colourrecognition respectively, plus shadenumber between 1.2 and 5.

IR filters - see BS EN 1714- minus code number for IR filters, plusshade number between 1.2 and 10.

Sunglare - see BS EN 1725- or 6- minus code number for sunglarefilters without or with IR specificationrespectively, plus: shade numberbetween 1.1 and 4.1 and BS EN 1836.

Optical class1, 2 or 3 - indicates optical quality ofthe ocular. Class 1 is the best.

Standards for eye and face protection

Mechanical strength - marked on framesand/or oculars

Symbol Property

S Increased robustnessIncreased robustness(oculars only)

F High speed particles, lowenergy impact (any type)

B High speed particles, mediumenergy impact (goggles andfaceshields only)

A High speed particles, highenergy impact (faceshieldsonly)

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Frames

Symbol Property

3 Resistant to liquid droplets(goggles), or liquid splashes(faceshields, but not mesh)

4 Resistant to coarse dustparticles

5 Resistant to gas and fine dustparticles

9 Resistant to molten metalsand hot solids

G Resistant to radiant heat(BS EN 1731 faceshields only)

Oculars

Symbol Property

8 Resistant to short circuitelectric arc (faceshields only)

9 Resistant to molten metalsand hot solids (goggles andfaceshields only)

Other ocular markings

Symbol Property

K Resistant to surface damageby fine particles

N Resistant to fogging

G Resistant to radiant heat(BS EN 1731 faceshields only)

BS EN 1731:2006. Personal eye protection.Mesh eye and face protectorsNote: The requirements and markings forradiant heat, which appear in BS EN1731:1998, have been deleted from thisstandard.

The order of markings (following EN166),where applicable, is:• Manufacturer’s mark • BS EN 1731:2006 • Mechanical strength

Mechanical strength: S, F, B or A - as forBS EN 166

Fields of use

Fire fighters and emergency teams

BS EN 14458:2004 - Faceshields and visorsfor fire fighters, ambulance andemergency services

Symbol Property

= General (non-fire fighting) use

+ Fire fighters’ use

Face guard, or eye guard

Options: Scale number appropriate tofiltering performance (see EN 166)

Temperature extremes of testing

Symbol Property

T Resistance to medium energyimpact at extremes oftemperature

A Resistance to high energyimpact

AT Resistance to high energyimpact at extremes oftemperature

K Resistance to abrasion

N Resistance to fogging

R Enhanced infrared reflection

Ω Electrical properties

Sport

BS EN 174:2001 - Ski goggles for downhill skiingFiltering oculars marked according totransmittance:S# - in range S0 to S4. Higher numberindicates lower transmittance

BS 7930-1:1998 - Eye protectors for racketsports - Squash OcularsThe order of other markings is:• Manufacturer identification• Standard number (BS 7930-1)

FramesThe order of other markings is:• Manufacturer identification• Standard number (BS 7930-1)• Model size if applicable

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Industrial prescription protective eyewear

Assessment of requiredprotective eyewearHealth and Safety at Work Regulationsrequire the employer to identify andevaluate workplace risk. This is commonlyundertaken by the company safetyofficer. The reason for this is that in orderto do a comprehensive assessment,someone with access to, and familiaritywith, the working environment is essential.This effectively means that apractice-based optician is not theappropriate person to assess such risk,though they may well dispense therequired protective eyewear.

The net result of this is that the patient willcome into the practice with a ‘Company’order form. This will stipulate the type oflens and lens material required.

Note: If this is not stipulated contactthe company health and safety officerbefore proceeding. The frame may alsobe specified though, frequently, achoice is offered to the patient from astipulated range.

On occasions, however, a self-employedtradesman may come into the practicerequiring protective eyewear. In thisinstance the optician should perform adetailed assessment of the patient’srequirements and the type of hazards

that are associated with their day today work. If it is feasible contact a localcompany involved in the same, or verysimilar, work type. Alternatively theoptician should contact a supplierinvolved in the supply of protectiveeyewear to seek their advice. Howeverwhen the optician proceeds, he/sheshould keep detailed case records ofthe reasons for their choice of lenses andframes supplied.

Once an order has been establishedthe spectacles must be ordered froma recognised safety eyewearmanufacturer. This will ensure that thenecessary standards are met and that aproper certificate is issued at the timeof completion.

The norm when ‘Company’ safetyspectacles are being supplied is that theoptician will receive a fee for thedispensing service. There are no specificamounts established for the dispensingservice so this should be agreed with thesupplier before proceeding.

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Care of protective eyewearNot all responsibility lies with the employer.The wearer has obligations to wear theprotective eyewear when required andin the manner that they were issued for.The wearer, or another party, must notinterfere with, abuse, or alter theappliance in any way.

Advice on the proper care of theappliance should be given (how to cleanand the benefits of putting into the caseprovided when not in use). Never useacetone or methyl chloride to cleanpolycarbonate.

Avoid extreme heat (unless specificallydesigned for such use) and humidity.

It is very important that the optician isaware of the very limited actions thatthey can perform with regard toprotective eyewear; effectively this islimited to adjustment only. The opticianmust never undertake any repair - evenreplacing a screw. Such action wouldinvalidate the protection guarantee. Allrepairs must be returned to the originalsupplier who will, when completed, issuea new guarantee certificate.

Sunglass tints will reduce lighttransmission, but should offer protection from hazardous radiation,depending on the tasks and environmentfor which they will be worn.

Ultra-violet (UV)Almost all solar UV radiation is absorbedfirstly by the earth’s ozone layer andthen by the anterior structures of the eye.A very small amount reaches the retina. UV absorption by the eye may contributeto age-related and other changes in theocular tissue and a number of seriouseye conditions.

UV is classified according to wavelength:

• UVA(315 nm – 380nm) - possiblecataract formation, skin cancer and/orretinal damage with long termexposure.

• UVB (280nm – 315nm) can damage thecornea, the conjunctiva and thecrystalline lens. ‘Snow-blindness’ isextreme photo-keratitis caused by UVB.

• UVC (100nm - 280nm) is absorbed bythe ozone layer.

Infra-red (IR)Opinions are divided on the damagecaused by IR to ocular tissue, even undervery bright solar illumination. IR protectionis essential in industrial environments whenIR radiation exposure is extreme.

Blue light (380nm - 500nm)Sometimes referred to as high-energyvisible light (HEV), some sources claimevidence for damage to ocular tissue byblue light.

The standards which refer to the blue lighthazard state that there is little short-termrisk associated with exposure to blue light,but that the long-term risk could begreater.

There are two important standards thatshould be consulted for informationrelated to dispensing spectacles for sunprotection:

1) BS EN ISO 8980-3:2013 Ophthalmicoptics - Uncut finished spectacle lensesPart 3: Transmittance specificationsand test methods

2) BS EN ISO 12312-1:2013 Eye and faceprotection - Sunglasses and relatedeyewear - Part 1: Sunglasses forgeneral use

Although only BS EN ISO 8980-3 relatesspecifically to prescription lenses, BS ENISO 12312 contains specifications whichshould be applied to all sunglasses.

New in the standards is the minimumspecification for lens size in order toadequately protect the eye;

Sunglass protection

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40 28 for adults and 34 24 specified forchildren. Also specified is the requirementfor temporal shielding for category 4 tintsso that the light transmittance around thesunlens is not greater than that at thevisual point.

Note: BS EN ISO 8980-3 states that ‘Spectacle lenses with a luminoustransmittance less than 75% shall not be usedfor road use and driving in twilight or at night.’

This specification overlaps somewhat withthe filter categories, but nevertheless isthe most up-to-date directive.

There are additional requirements fordriving sunlenses regarding traffic signaldetection, so it should be ensured bydiscussion with the manufacturer that thetint dispensed complies. The best adviceshould be for no tinting to the lens, but anMAR coat should be a must (perhaps agold reflex, an arguable aid to contrast).For users working long hours underfluorescent lighting, a blue reflex may behelpful to counter the tiny amount of UVemitted from this type of lighting.

• Driving and road use - Filters suitable fordaylight are: 0, 1, 2 and 3

• Filters from 1 - 4 are not suitable for nightdriving and road use

• Filter category 4 not suitable for drivingor road use per se

Although the above filter categories referto plano sunglasses the information isalso very relevant to prescriptionsunglass wear.

Other specialist sun protection lenses

PolycarbonateWhere safety or wrap around types arerequired polycarbonate is commonlyused (polycarbonate, in white form,eliminates 100% of UV @ 380nm).

Polarised lensesWhich are the only truly anti-glare lenses,should be recommend for use on andaround water (fishing, sailing, water skiingetc). For prolonged wear, there is a veryvalid argument for the addition of a mirrorcoating, to counteract the increased UVbeing reflected from the water. It is also avery good driving/road use tint, especiallyin wet conditions on a bright/sunny day.Consideration should also be given to‘DriveWear’ lenses (for daytime use only),which combine photochromictechnology with polarisation.

Filter Description Range of luminous transmittancecategory from over to

0 Clear or very light tint 80% 100%

1 Light tint 43% 80%

2 Medium tint 18% 43%

3 Dark tint 8% 18%

4 Very dark tint (not suitable for driving or road use in any conditions) 3% 8%

Snow SkiingEye protection for skiing is usually used ingoggle form and, where a prescription isrequired, inserts may be fitted.

Snow reflects visible and UV light,increasing the overall brightness. In sunnyconditions very dark brown tints can bedispensed.

BS EN ISO 12312 states ‘…in extremelyhigh luminance conditions, such as desertand snowfields under full sunlight, the useof category 4 filters may berecommended.’

For overcast, flat light days, in which thereis an over-abundance of blue light,yellow or rose tints may be used. Greytints reduce transmittance across thespectrum. Polarised lenses may also beused, but these tend to mask smallcontours on the slope. Visible and UVtransmittance may also be furtherreduced by the use of mirror coatings.

Shooting / archeryA bronze tint should be used for skeet,clay-pigeon and trap shooting. It is alsothe tint of choice for hunting.

For black on white target shooting yellowtints offer good contrast. However, targetsmay vary in colour. For orange targets usean orange tint. Red and pink tints aregood for black and green targets andare also effective on orange targets andfor hunting; they also reduce the effectsof a green background, grass, trees andshrubs. A red tint can improve colourdifferentiation for people with a colourvision problem.

Tints should not be too dark, as thisresults in an enlarged pupil, which canadversely affect the shooters’/archers’performance. Compare this to thepinhole effect, which sharpens theimage.

Sunglass protectionContinued

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CricketTints will vary according to the lightconditions, but the purpose is mainly toenhance contrast. The spectacles aremostly wrap around and will benefit froma mirror coating (cricketers spendprolonged periods in the field increasingUV exposure).

Tropical/desert useAccording to BS EN ISO Standards, IRradiation on the ground, even underextreme illuminance conditions, poses norisk to the ocular tissues. Prolongedexposure in desert environments may,however, pose some risk according tosome scientists. Protection from infrared isachieved by the use of ferrous oxide inthe glass lens mix, eg Rayban G15.However, as the G15 is a solid glass tintdiffering thicknesses in the lens will result inan uneven tint. This can be addressedwith bonded/equitint forms.

Photochromic lensesPhotochromic lenses should berecommended for patients who aregenerally light sensitive, who like aflexibility in their tint, or for pathological/genetic conditions, such as albinism.

DIYThe DIY amateur is just as vulnerable toaccident as the professional, arguablymore so. He/she should be encouragedto have the necessary eye protection.Hazards may include flying particles, dust,chemical compounds (ammonia, acids,super glue). Is it surprising that there aremore accidents in the home than atwork? The emmetrope should wear wraparound goggles (injection mouldedpolycarbonate). The spectacle wearershould at least have some form of overprotection.

Hard ball and racket sportsFor ‘hard’ ball and racket sports impactresistance is the prime concern.Hard resin CR39 may be used, butpolycarbonate or Trivex are preferable.

SquashSquash is particularly hazardous, as thesquash ball is almost equal in size to theeye's orbit, therefore orbittal fractures area common injury. All squash playersshould have eye protection. There arespecifically designed goggles for squashuse which must be fitted with the mostefficient impact resistant lenses.

Swimming gogglesPoor vision and the salt or chlorine inwater can make swimming anuncomfortable experience. Planoswimming goggles are available, as areready-wear prescription goggles,incorporating basic spherical lens powers,or goggles with the patient's accurateprescription incorporated. Impactresistance is a consideration, thoughCR39 material should be adequate.

Sports and home protection

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Diving (scuba and snorkeling) The protection of the ocular area is a veryimportant factor, hence normally a facemask is supplied (a firm water-tight fit isessential). Plano masks are available; forprescription use masks with inserts may beused or the prescription lens may bestuck/cemented to the rear surface ofthe mask with accurate centration.

Cycling Cycling has many facets to considerwhen supplying the protective unit, whichare most commonly supplied in goggleform because this offers good all roundprotection. These are obtainable in planoform and as goggles which are fitted withprescription inserts or as prescription lensgoggles using freeform technology. Thetint choice is an important factor from thelight transmission to UV protection tocontrast requirements. Protection fromwind, dust and impact are also essential.Vitally important is a firm and stable fit.

FootballAttention should be drawn to theABDO ‘Children’s eye protection infootball’ publication, a guide forreferees, coaches and parents. This isavailable upon application and is freeto ABDO members.

These are just some of the types ofspecialised eyewear encountered inpractice. However, with responsibilitycomes liability, so always keep detailedpractice records, even when supplyingnon-prescription units.

Association of British Dispensing Opticians199 Gloucester Terrace, London W2 6LDTelephone 020 7298 5100 Fax 020 7298 5111 Email general@abdolondon.org.ukWebsite www.abdo.org.uk

www.twitter.com/MembershipAbdo

Author: Ted Moffatt FBDO

(with appreciation to Paula Stevens forher valued help and advice)

Acknowledgements and thanksBritish Standards Institution Safetyspecs.co.ukSpecsaversThe Norville Group

As standards are subject to regularupdates and changes, please note theinformation in this brochure is onlyaccurate at the time of going to press.

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