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Jason Britton 1 , Ewan Eadie 2 , David Turner 3 1 Leeds Teaching Hospitals, Medical Physics

An investigation of different types of eyewear and face shields in protecting patients and operators from the harmful effects of Ultraviolet Radiation. Jason Britton 1 , Ewan Eadie 2 , David Turner 3 1 Leeds Teaching Hospitals, Medical Physics 2 Ninewells Hospital Dundee

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Jason Britton 1 , Ewan Eadie 2 , David Turner 3 1 Leeds Teaching Hospitals, Medical Physics

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  1. An investigation of different types of eyewear and face shields in protecting patients and operators from the harmful effects of Ultraviolet Radiation Jason Britton1, Ewan Eadie2, David Turner3 1 Leeds Teaching Hospitals, Medical Physics 2Ninewells Hospital Dundee 3 Leeds Teaching Hospitals, Dermatology

  2. Overview • Background – why do we need protective eye wear and face shields • Problems encountered • Measurement methods – Dundee and Leeds • Results • Discussions • Conclusions

  3. Background – protecting patients • Patients will wear face shields to guard their eyes from UVR • Face shields may also be worn with opaque personal protective equipment (PPE) • Protective eyewear is also worn by patients for 24 hours following ingestion of psoralen. • No exposure limits for UVR exposure • Ocular exposure to UVR is kept as low as possible, • Bellow the limits published in the ICNIRP Guidelines [1]. • Guideline eyewear transmission limits for patients who have ingested psoralen are; 10% at 390 nm, 5% at 380 nm, 2% at 370 nm and 1% at wavelengths shorter than 360 nm [2].

  4. Background -operators • May also be required by employees when undertaking measurements of the phototherapy devices or when managing patients. • Every effort is made to put in place control strategies which reduce or negate its requirement. • Risk assessment is required to ensure employee eye and skin exposure to UVR is below legal limits • The occupational exposure limits for UVR between 180 nm - 400 nm, incident on the unprotected eye(s) and skin should not exceed 30 J/m2 when spectrally weighted using the appropriate factors [3].

  5. Why assess face shields and protective eyewear? • There are a number of different types of protective eyewear and face shields available for purchase • Some have clear identifications that show the levels of protection provided and the wavelength range. • May not be as clearly marked or include a medical CE mark but may conform to EN166 and EN170. • Maybe • Just as Effective at protecting the eyes • More robust • Significantly cheaper than those sold with a CE marking.

  6. Example • One type of face shield costs £70 with a CE mark but exactly the same make and model was available for £15.95 from a different distributor but did not carry the CE mark. • No differences in the design, UVR attenuation characteristics and construction of the two face masks.

  7. Method - Leeds • Newport Solar Simulator used to generate broadband light from 270 nm – 700 nm. • Collimated 10 cm x 10 cm beam shaped by an atmospheric attenuation filter. • Measurements made with AvaSpec-ULS2048 spectrometer • Series of measurements was made using to assess the transmission characteristics of the Personal Protective equipment: • Dark background measurement • Un-attenuated output from the solar simulator. • Output from the solar simulator when attenuated by the different type of personal protective equipment.

  8. Face shields and eyewear tested in Leeds

  9. Dundee Method 1 • 6 broadband UVA lamps (R-UVA, Philips, Netherlands) as typically used during photo-chemotherapy. • Double grating scanning Bentham spectro-Radiometer • Atemperature controlled laboratory. • Bank of UVA lamps was placed mid-height at a distance of 30 cm from the entrance optics • 315 nm to 400 nm in 1 nm increments. • PPE was then placed directly in front of the optical diffuser of the spectroradiometer • Ratio of the signal (nano-Amps(na)) provided the spectral transmission properties of the product.

  10. Dundee Method 2 • Same 6 broadband UVA lamps • Double chamber U-3900 spectrophotometer (Hitachi High-Technologies Corporation, Japan) • Sample is placed within the spectrophotometer in one of the two beam paths and the relationship between unobstructed and obstructed beam path is measured at each wavelength interval. Chamber is much smaller than the face masks, only a single mask was tested with this method by dissecting a small piece • Protective spectacles were all measured using this method

  11. Face shields and eyewear tested in Dundee

  12. Centre Inter-comparison • For quality control purposes both laboratories measured the transmission properties of the Honeywell and the Centurion S592 • Each laboratory had a separate example of Honeywell Bionic but the same Centurion face mask was investigated at each centre.

  13. Results

  14. Leeds – transmission values face shields

  15. Leeds – Protective Eyewear – Transmission Values

  16. Dundee Face shield measurements – method 1

  17. Dundee – protective eye wear measurements – method 2

  18. Spectrophotometer and Spectroradiometer- Dundee

  19. Comparison for Honeywell Bionic and Centurion Face shields

  20. Suitability as sunglasses - Leeds

  21. Suitability as sunglasses - Dundee

  22. Discussion (1) • Provide protection to the patient or operator between 300nm and 400nm with transmission values less than 10% across these wavelengths • Face shields & Protective eyewear (Leeds) • Oberon UVP803 • Centurion Clear • Goggles/protective spectacles • Spectranetics • Athrodax red • BolleSilium

  23. Discussion (2) • Face shields and Protective eyewear (Dundee) • Centurion Green • Centurion Clear • Oberon UVP803 • Goggles/protective spectacles • 3M Yellow • UVEX Orange • Most expensive examples tested as part of these experiments, the Honeywell Bionic and Sibille face shields do not fully attenuate UVR between 350 and 400nm..

  24. Discussion (3) • Majority of the protective face shields and eyewear meet the requirements for sunglasses according to the criteria set by the British Association of Dermatologists. The only protective eyewear that does not meet the criteria are: • The Bolle face shields tested at each centre, • The Honeywell Bionic Electric Arc • The Sceptre face shield • The Hybec Durham Medimask

  25. Conclusions • It is evident from these results that price and material used to construct the UVR face shields should not be the main factors when deciding on the purchase of new face shields and protective eyewear. • Incumbent on UVR dermatology treatment centres to undertake their own assessment • It is hoped that the data from these investigations will be useful in making future purchasing decisions • Dundee and Leeds now purchase Centurion Clear face shield as the Oberon UVP803 was no longer available, • The ‘3M yellow’ and the athrodax red goggles for use as protective eyewear

  26. References • [1] The International Commission on Non-Ionizing Radiation Protection Guidelines on Limits of exposure to Ultraviolet Radiation of wavelengths between 180nm and 400nm (Incoherent optical radiation); Health Physics 87(2):171-186; 2004 • [2] Moseley, H., Cox, N.H., Mackie, R.M. The suitability of sunglasses used by patients following ingestion of psoralen. British Journal of Dermatology; 118:247-253; 1998 • [3] The Control of Artificial Optical Radiation at Work Regulations; 2010 No. 1140; http://www.legislation.gov.uk/uksi/2010/1140/pdfs/uksi_20101140_en.pdf; accessed 10/08/2018

  27. Thank you for listening

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