"Please don't touch the art" is a warning drummed into every single museum visitor.

Paintings on walls across the world are normally looked at from a distance and with hands very firmly tucked away.

But for a select pair of conservationists at the National Museum Wales in Cardiff their very job is to touch, look after, and restore some of the priceless artworks held at the prestigious site.

From 20th Century masterpieces worth millions of pounds to more modern pieces, Kitty McKenny and Adam Webster are responsible for maintaining the collection at one of Wales' most famous museums.

Kitty McKenny working on one painting

The job involves huge amounts of preparation, very careful hand movements, and filling out insurance forms with plenty of zeroes.

Kitty and Adam work in probably the best office of the whole museum.

The long, tall room on the top floor is full of natural light needed to work on the various paintings lined up on easels throughout the studio.

One painting showing a restored section on the left and an unfinished section on the right

The quiet room doesn't normally see many visitors but it has been host to famous art works from Van Gogh to Monet.

Very few people will have ever touched the paintings that come through the studio and Kitty and Adam see their work as an honour.

After an art degree and then a master's in painting conservation, followed by plenty of internships, Kitty started work at the museum around three years ago.

The studio Adam and Kitty work in

Senior paintings conservator Kitty said: "In my head I'm just trying to keep myself moving as slowly as possible. It's like tai chi up here whenever I'm moving a painting from A to B.

"You kind of have to reign in all your natural clumsiness and just be really mindful of what you're doing. So plan every movement, always wear your gloves, and just don't take any risks. 

"Whenever you see them out of their frame they're just so naked and so vulnerable-looking. 

"They kind of look quite robust when they're in their frames but whenever you get them out and it's just like a Monet and it's just a piece of material attached to a wooden frame it's just a wonderful experience. It's a real honour, it's incredible."

Before they even think about restoring a painting – or even touching it – the pair will carefully study everything about it and create a thought-out plan. 

It’s photographed, scanned, and even X-rayed before they’d even think about working on a piece.

The studio has had some very famous guests

Kitty said: "When a painting comes in, first of all I would create a condition log for it. 

“I'd photograph it and with ultraviolet light too. That will tell me if there's any interesting resins in the paint layer, it'll tell me if there's a varnish layer. 

"If possible I like to look at them in infrared light too which will show me if there is any under-drawing.

“After that I will generate a condition report and that's where I'll log all my thoughts and findings and I'll also create a potential treatment plan.”

By X-raying a painting they can even discover hidden drawings underneath unseen for hundreds of years.

Chief conservator Adam said: “If we think the painting may have something else below it it's a nice chance to do an X-ray and that will show us if there's any heavy-metal base under-layers. So you can get quite a nice picture of how the painting was created.”

When a painting in the collection isn’t on display, out on loan, or being restored, it’s usually kept in a huge room underneath the museum. 

One room in the sprawling underbelly of the museum is home to dozens of artworks carefully hung on sliding rails with the temperature and humidity carefully monitored.

Dozens of paintings are kept on sliding rails under the museum
Inside the storage room

Every aspect of caring for these paintings is carefully measured and they're often talked about more like people than pieces of art.

From seeing them "naked" without their frames to Adam describing how it can be "traumatic" for a painting to sent away on loan, these are more than just drawings on pieces of canvas. 

The only difference is that they're probably far better insured than most people are. 

Kitty said: "They always say at conservation school to try and not learn how much something is worth but being here and filling out the indemnity forms before something goes out on loan I do see the prices of the Monets and other famous pieces and it just blows your mind."

One of the biggest challenges Kitty and Adam face is dealing with restorations carried out years ago that end up causing more issues.

But before they start working on a painting Adam explained how there is plenty of thinking, planning, and small testing to be done first.

The pair often study very small samples of paintings

Kitty explained: "When you're removing a varnish layer from an old painting, which often they do need to be removed because it can yellow in light, in order to remove the varnish without removing the oil paint below it's a case of what can work with lots of little tests."

Some of the conservation methods used previously have left paintings brittle, difficult to look after, and not looking how the artist intended.

Kitty added: "Our main core principles now are minimum intervention so doing as little as possible and also reversibility.

"The materials that we use to varnish a painting and retouch a painting are modern synthetic versions which are non-yellowing and they'll always be easy to remove."

Despite the advances in conservation there are still some trusty methods that haven't dated.

Kitty explained how one of the best ways to surface clean a painting is to use a cotton swab and saliva.

She said: "It's so great – it's warm, it's an enzyme, and it's fantastic at removing organic dirt. And then we always clear it off with ionized water – so it's not gross."

One thing that has definitely changed is how they source the paint itself. A lot of the masterpieces held at the museum feature pigments made from bizarre materials including everything from ground-up glass to lead and even Egyptian mummies.

Kitty said: "The pigments we use nowadays may not exactly match the ones they would have used back then. Some of the pigments they had back then, they wouldn't exactly match our standards of animal safety now.

"There's a pigment called Indian yellow and genuine Indian yellow is made from the urine of cows that were only fed mango leaves. Then the urine was evaporated off and you got these amazing yellow 'cakes' which were wonderful but basically the cows were starving – so that's not used anymore.

"There was also a pigment back then which was called 'mummy brown' and it was made of ground-up Egyptian mummies. 

"I think there were so many of them back then – and it did create this lovely warm brown colour."

All of Adam and Kitty's work is to ensure that the paintings are shown in their best possible light to the hundreds of thousands of visitors each year.

Kitty added: "If I need a five-minute break I'll take a quick jaunt around the galleries and see how people interact with the paintings.

"Sometimes I just stand back – it's lovely to work on a painting and then see other people look at it when it's back out in the gallery."