Sun exposure of indoor workers in the UK - survey on the time spent outdoors.

Assessment of ultraviolet (UV) exposure is essential for evaluation of the risks and benefits to optimise public health outcomes. The exposure depends on available environmental UV radiation and individual behaviour, and it can be obtained from dosimetry studies; however, the use of dosimeters is often not feasible for large population groups or over long periods of time. In this study, a lifestyle questionnaire has been used to obtain information on the time spent outdoors by indoor workers that could be used in combination with dosimetry studies in smaller targeted groups to quantify UV exposure for health risk/benefit analysis. 894 office and laboratory workers at the Public Health England, UK, responded to the survey. Questions addressed the time of day and the duration of time; staff were outdoors on weekdays, at weekends and during holidays. The majority of the responders spent negligible time outdoors on weekdays. Outdoor activities before and after work were constrained by the work pattern and commuting. The average time for those who go outdoors before and after commuting was 22.5 ± 16.2 min and 30.4 ± 21.4 min, respectively. Only 7% of participants regularly spent their lunch break outdoors for 21.5 ± 12.2 min and weekday exposure may contribute less than 13% of the daily available erythema dose. At the weekend, on average responders spend 5.0 ± 2.6 h outdoors over the two days: if taken around midday, it accounts for approximately 50% of available UV exposure. In winter months in the UK, November to March, the combination of very low environmental UV and low ambient temperatures results in negligible UV exposure. Holidays contributed to the majority of the annual UV exposure. In summer, 45% of responders went to destinations where the UV levels may be up to 2 times higher than in the UK; durations of overseas holidays are also longer than UK breaks. The UV dose from two weeks of holiday in extreme UV index level destinations could be comparable to a 1.5-2 summer months holiday in the UK. The survey data were validated with 6 months of dosimetry within the same cohort; very strong and strong correlation was found between the survey and measurements. This shows that a lifestyle survey can be used in combination with targeted dosimetry studies in small groups to obtain information about the time spent outdoors.

Use of illuminance as a guide to effective light delivery during daylight photodynamic therapy in the U.K.

BACKGROUND: Daylight PDT (dPDT) is an effective and nearly painless treatment for field-change actinic keratosis. Measuring the protoporphyrin-IX (PpIX)-weighted exposure dose can give an indication of when conditions are most viable for effective dPDT. It would be advantageous for practitioners if more detailed information of exposure dose and appropriate treatment conditions were available. Where sophisticated measurement equipment is unavailable, simpler and more cost-effective methods of dose measurement are desirable. OBJECTIVES: To devise a model whereby illuminance data can be converted into PpIX-weighted exposure dose, and to use this model to estimate appropriate times for dPDT across the U.K. and Ireland. METHODS: Spectral irradiance data were analysed to obtain a conversion model for illuminance to PpIX-weighted dose. This model was applied to historic illuminance data from nine sites to obtain PpIX-weighted dose across the U.K. and Ireland. Temperature data and an analysis of conservatory-based dPDT were also considered. RESULTS: Distribution of the expected PpIX-weighted dose across the nine locations is presented. Temperature data showed that it could be too cold for dPDT, even when there is sufficient light exposure. Conservatory-based dPDT could extend the times in the year for possible treatment. CONCLUSIONS: This proposed conversion model provides a means of using an illuminance reading to calculate the PpIX-weighted exposure dose. Dosimetry of dPDT may be carried out simply and at low cost using the presented method; however, the results presented may be used as a guide for those considering dPDT, without the need to conduct measurements themselves.

Validation and in vivo assessment of an innovative satellite-based solar UV dosimeter for a mobile app dedicated to skin health.

We present an innovative satellite-based solar UV (ultraviolet) radiation dosimeter with a mobile app interface that has been validated by exploiting both ground-based measurements and an in vivo assessment of the erythemal effects on some volunteers having controlled exposure to solar radiation. The app with this satellite-based UV dosimeter also includes other related functionalities such as the provision of safe sun exposure time updated in real-time and end exposure visual/sound alert. Both validations showed that the system has a good accuracy and reliability needed for health-related applications. This app will be launched on the market by siHealth Ltd in May 2016 under the name of "HappySun" and is available for both Android and iOS devices (more info on ). Extensive R&D activities are on-going for the further improvement of the satellite-based UV dosimeter's accuracy.

Safety of light emitting diodes in toys.

Light emitting diodes (LEDs) are increasingly being used in toys. An assessment methodology is described for determining the accessible emission limits for the optical radiation from the toys, which takes account of expected use and reasonably foreseeable misuse of toys. Where data are available, it may be possible to assess the toy from the data sheet alone. If this information is not available, a simple measurement protocol is proposed.

A survey of the optical hazards associated with hospital light sources with reference to the Control of Artificial Optical Radiation at Work Regulations 2010.

Workplace exposure to coherent and incoherent optical radiation from artificial sources is regulated under the Artificial Optical Radiation Directive (AORD) 2006/25/EC, now implemented in the UK under the Control of Artificial Optical Radiation at Work Regulations (AOR) 2010. These regulations set out exposure limit values. Implementing the AOR (2010 Health and Safety Statutory Instrument No 1140 www.legislation.gov.uk/uksi/2010/1140/pdf/uksi_20101140_en.pdf) requirements in a hospital environment is a potentially complex problem because of the wide variety of sources used for illumination, diagnosis and therapy. A survey of sources of incoherent optical radiation in a large hospital is reported here. The survey covers examples of office lighting, operating theatre lighting, examination lamps, and sources for ultraviolet phototherapy and visible phototherapies, including photodynamic therapy and neonatal blue-light therapy. The results of the survey are used to inform consideration of the strategy that a hospital might reasonably adopt both to demonstrate compliance with the AOR (2010) and to direct implementation effort.

Optical radiation emissions from compact fluorescent lamps.

There is a drive to energy efficiency to mitigate climate change. To meet this challenge, the UK Government has proposed phasing out incandescent lamps by the end of 2011 and replacing them with energy efficient fluorescent lighting, including compact fluorescent lamps (CFLs) with integrated ballasts. This paper presents a summary of an assessment conducted by the Health Protection Agency in March 2008 to evaluate the optical radiation emissions of CFLs currently available in the UK consumer market. The study concluded that the UV emissions from a significant percentage of the tested CFLs with single envelopes may result in foreseeable overexposure of the skin when these lamps are used in desk or task lighting applications. The optical output of all tested CFLs, in addition to high-frequency modulation, had a 100-Hz envelope with modulation in excess of 15%. This degree of modulation may be linked to a number of adverse effects.

Assessment of sun protection for children's summer 2005 clothing collection.

Overexposure to solar ultraviolet radiation (UVR) in childhood is considered to be a critical factor for developing skin cancer in later life. Clothing may offer a simple and effective means of protection against overexposure to the sun, but its use has often been underrated in public opinion. The Health Protection Agency, in close collaboration with a number of UK retailers, conducted a study to evaluate the UVR protection characteristics of the summer 2005 collection of children's clothing for outdoor activity. The current paper presents a summary of the assessment and the effects of stretching and wetting on the Ultraviolet Protection Factor (UPF) rating of children's clothing. The results demonstrate the need for better public guidance in sun protection of children and more comprehensive evaluation procedures for sun protection provided by clothing.

Radiation and chemical degradation of UVR protection characteristics of fabrics.

Clothing can provide substantial protection against solar ultraviolet radiation (UVR) and quantifying the amount of protection can have useful applications to recreational, occupational and medical situations. However, exposure of fabrics to sunlight and sea water can alter their physical and chemical properties, resulting in a change of UVR attenuation characteristics. The objective of the current study was to evaluate the effects of environmental degradation of fabrics on their UVR protection characteristics. The methodologies applied in this study can be used also for the assessment of protective clothing against occupational exposure.

A new methodology for the assessment of hand protection from ultraviolet exposure.

A number of industrial applications and public services involve occupational exposure to ultraviolet radiation (UVR) from a variety of lamps and lasers. The aim of this study was to develop a methodology for the assessment of the UV protection level for disposable gloves. Glove UV protection factor is defined as a time-scale increase in exposure permitted for the hand protected by a glove with respect to an unprotected hand. Our study showed that for all tested gloves a change in UVR attenuation with stretching is characteristic for the type of glove material and can be included as a scaling factor in the definition of UVR protection. Glove material has a bigger effect on UVR protection level than variations in the glove thickness or its colour. Examples of assessment of the 'worst case scenario' are compared with the protection level against a number of sources, together with the guidance on a simplified evaluation protocol. An application-specific assessment, illustrated for 'SmartWater' forensic examinations and biological trans-illuminators, demonstrates that some gloves provide inadequate protection against occupational UV exposure.

Low-energy light bulbs, computers, tablets and the blue light hazard.

The introduction of low energy lighting and the widespread use of computer and mobile technologies have changed the exposure of human eyes to light. Occasional claims that the light sources with emissions containing blue light may cause eye damage raise concerns in the media. The aim of the study was to determine if it was appropriate to issue advice on the public health concerns. A number of sources were assessed and the exposure conditions were compared with international exposure limits, and the exposure likely to be received from staring at a blue sky. None of the sources assessed approached the exposure limits, even for extended viewing times.

Methods of dark signal determination for CCD array spectroradiometers used in solar UVR measurements.

The methods of the dark signal determination by direct contemporaneous measurements using a light spectrum and modelling of the dark signal based on the dark signal characterisation data were discussed. These techniques were tested with two charge-couple detectors (CCD) array spectroradiometers used in solar UVR measurements. The sensitivity of both instruments was significantly reduced when shutters were used; the measured signal varied by up to 12% depending on the orientation of the shutter. The shutters should be permanently attached to the SSR, so that the orientation cannot be changed to prevent an increase in uncertainty. The method of using blind pixels from the optically inactive part of the CCD array in a light spectrum could be used to derive the dark signal with some limitations for integration times <10 s for the QE65000. An alternative method of deriving the dark signal from light measurements using out-of-range pixels has been proved impossible due to out-of-range stray light in both instruments. The dark signal was characterised for the range of integration times and ambient temperatures of 15-35°C. Based on these data, the model of the dark signal was developed so that a single value of the dark signal can be subtracted over the whole spectral range if the instrument temperature is known.

[Periodicity of chickenpox and epidemic parotitis]. / O periodichnosti vetrianoi ospy i épidemicheskogo parotita.

The pattern of the dynamics of incidence of chickenpox and epidemic mumps in Leningrad for many years was studied. The application of mathematical methods of treatment of the incidence data revealed the main trends of the processes and the occurrence of three rhythms in each infection. The average values of the periods of these rhythms differ for chickenpox and epidemic mumps and are 11.0, 6.2, and 4.1 years and 8.2, 4.0, and 2.8 years, respectively. The study of the age incidence in comparison with the dynamics of the epidemic process for many years showed that periodicity of these infections could not be explained completely by variations of the herd immunity of the population.

Occupational UVR skin protection by make-up.

New legislation has been introduced in the Member States of the European Union, covering worker exposure to artificial optical radiation. Use of make-up could reduce the ultraviolet hazard level and provide additional protection for skin against UV radiation (UVR). This is particularly important in entertainment and filming where intentional exposure of the actors and presenters to the very intense light sources may be required for extended periods of time. This document presents the assessment of UVR protection of make-up used in entertainment and demonstrates that the protection level varies considerably for different luminaires and application techniques. An important practical implication of this finding is that make-up alone cannot be considered as a reliable protection measure against skin exposure to actinic UV.

Assessment of personal exposures to optical radiation in large entertainment venues.

Workplace exposure to optical radiation from artificial sources is regulated in Europe under the Artificial Optical Radiation Directive 2006/25/EC implemented in the UK as The Control of Artificial Optical Radiation at Work Regulations 2010. The entertainment environment often presents an extremely complex situation for the assessment of occupational exposures. Multiple illumination sources, continuously changing illumination conditions and people moving during performances add further complexity to the assessment. This document proposes a methodology for assessing the risks arising from exposure to optical radiation and presents detailed case studies of practical assessment for two large entertainment venues.