Daily Bulletin

The Conversation

  • Written by Noushin Nasiri, Postdoctoral Research Fellow, School of Mathematical and Physical Sciences, University of Technology Sydney
I've always wondered: do fluorescent lights emit UV, and can it harm me?

This is an article from I’ve Always Wondered, a series where readers send in questions they’d like an expert to answer. Send your question to alwayswondered@theconversation.edu.au

I’ve always wondered, should I be concerned about experiencing UV damage from fluorescent lights? Am I at risk of skin cancer or premature ageing if I work in an office building lit with fluorescent lights? – Damien, Canberra, 26

Ultraviolet radiation is the highest-energy component of the Sun’s rays that reach the Earth’s surface. UV light stimulates the synthesis of vitamin D, which is an essential compound for growth of bones and teeth, as well as improved resistance against certain diseases.

On the other hand, too much UV radiation is the main cause of melanoma, which is a malignant form of skin cancer. This is why you’ve always been advised to protect your skin with sunscreen.

But what about the lights indoors? Do fluorescent lights also emit UV?

Read more: I've always wondered: what's behind the belly button?

The best way to find the answer is to firstly understand how fluorescent lights work. Inside the bulb, electrical discharge excites a gas (usually neon or mercury vapour in argon), which emits ultraviolet radiation. But the ultraviolet radiation is not visible to human eyes and must be converted into visible light. This is done by the light’s interior fluorescent coating, which is able to absorb most of the UV radiation and emit lower-energy wavelengths in the visible spectrum.

But some UV rays get through the bulb, especially if the bulb’s internal coating is cracked, allowing more UV light to pass through. In fact many types of lighting used in our homes emit small amounts of UV radiation.

But according to the Australian Radiation Protection and Nuclear Safety Agency (ARPANSA), the UV emissions from most indoor light sources, including fluorescent lights, are below the approved Australian limits. This means they won’t cause any risk to health for normal people, if we use them properly.

Safe distances

The emissions from all sources of light decrease rapidly with distance. At a typical use distance (more than 25cm), the UV light emitted from fluorescent lights falls below the level of general concern for healthy individuals.

Read more: I’ve always wondered: why do our computing devices seem to slow down?

The only exception is a medical condition that makes you particularly sensitive to UV light. The vast majority of people do not suffer from such UV or visible light sensitivities.

Exposure time

The longer the exposure time, the higher the UV dosage absorbed by the skin. At a measurement distance of 10cm, an exposure time of less than eight hours would be safe for almost all types of lights.

Compare this to the permissible exposure limits (PELs) in typical midday summer sunshine, which is six minutes in Brisbane and seven minutes in Sydney and Melbourne.

The UV level absorbed by our skin after eight hours’ exposure to indoor lights, at a typical use distance (25cm), would be equivalent to just over a minute of midday solar exposure on a clear summer day in a city such as Sydney or Melbourne. This shows the risk to us is very small indeed.

Read more: I've always wondered: why do our veins look blue when our blood is red?

Does the fluorescent tube have a cover?

If you have to spend a lot of time under fluorescent light, make sure fluorescent bulbs have plastic diffusers over them. The glass and the coating inside the glass used in fluorescent lights already provide a UV filter, which further reduces the already low levels of UV.

So, if a standard fluorescent tube lighting source is shielded by a standard acrylic plastic diffuser, there’s rarely a risk for human health, even for people who are affected by light sensitivity.

* Email your question to alwayswondered@theconversation.edu.au * Tell us on Twitter by tagging @ConversationEDU with the hashtag #alwayswondered, or * Tell us on Facebook

Authors: Noushin Nasiri, Postdoctoral Research Fellow, School of Mathematical and Physical Sciences, University of Technology Sydney

Read more http://theconversation.com/ive-always-wondered-do-fluorescent-lights-emit-uv-and-can-it-harm-me-90317

Writers Wanted

I studied 5,000 phone images: objects were more popular than people, but women took way more selfies


Bad reactions to the COVID vaccine will be rare, but Australians deserve a proper compensation scheme


Pacific tourism is desperate for a vaccine and travel freedoms, but the industry must learn from this crisis


The Conversation


Prime Minister Interview with Ben Fordham, 2GB

BEN FORDHAM: Scott Morrison, good morning to you.    PRIME MINISTER: Good morning, Ben. How are you?    FORDHAM: Good. How many days have you got to go?   PRIME MINISTER: I've got another we...

Scott Morrison - avatar Scott Morrison

Prime Minister Interview with Kieran Gilbert, Sky News

KIERAN GILBERT: Kieran Gilbert here with you and the Prime Minister joins me. Prime Minister, thanks so much for your time.  PRIME MINISTER: G'day Kieran.  GILBERT: An assumption a vaccine is ...

Daily Bulletin - avatar Daily Bulletin

Did BLM Really Change the US Police Work?

The Black Lives Matter (BLM) movement has proven that the power of the state rests in the hands of the people it governs. Following the death of 46-year-old black American George Floyd in a case of ...

a Guest Writer - avatar a Guest Writer

Business News

Cybersecurity data means nothing to business leaders without context

Top business leaders are starting to realise the widespread impact a cyberattack can have on a business. Unfortunately, according to a study by Forrester Consulting commissioned by Tenable, some...

Scott McKinnel, ANZ Country Manager, Tenable - avatar Scott McKinnel, ANZ Country Manager, Tenable

InteliCare triple winner at prestigious national technology awards

InteliCare triple winner at prestigious national technology awards Intelicare wins each nominated category and takes out overall category at national technology 2020 iAwards. Company wins overal...

Media Release - avatar Media Release

Arriba Group Founder, Marcella Romero, wins CEO Magazine’s Managing Director of the Year

Founder and Managing Director of the Arriba Group, Marcella Romero, has won Managing Director of the Year at last night’s The CEO Magazine’s Executive of the Year Awards. The CEO Magazine's Ex...

Lanham Media - avatar Lanham Media

News Co Media Group

Content & Technology Connecting Global Audiences

More Information - Less Opinion