The Bankside Power Station was closed in 1981 leaving a handsome, and increasingly derelict, face-brick building in a prestigious spot by the side of the river Thames in the heart of the city of London.

After an expensive conversion the building reopened as the Tate Modern. “Modern” in that it features art produced since 1900. Here you will find works by Claude Monet, Henri Matisse, Pablo Picasso and Andy Warhol. However, the Tate also commissions new work.

On 12 October they opened a major new installation in the vast – completely insanely gargantuan – Turbine Hall. Ai Weiwei is a 53-year-old Chinese ceramicist and his Sunflower Seeds is nothing less than 100 million individually crafted and painted porcelain sunflower seeds poured onto the floor. These were produced by 1,900 skilled artisans from the city of Jingdezhen, famed for its production of Imperial porcelain, over a two-year period.

Until Thursday you could happily walk and play in the seeds. Kids lay on their backs to make sunflower seed angels, businessmen shrugged off their patent-leather shoes and strolled back and forth in their suits, young couples picnicked. It was delightful.

Since Thursday it is a health hazard.

Let’s get the technical stuff out the way. Silicosis is an incurable disease which results from long-term (10 years or more) exposure to low-levels of the fine dust that pervades ceramics factories or even mines. It is possible to develop it over a shorter period but you’d have to inhale an awful lot.

In addition, depending on the glaze used on the porcelain, you may also be exposed to minute traces of heavy metals from the tint.

If you have weak lungs, or are already suffering from lung disease or emphysema, then you’d want to stay away or wear a simple fabric mask.

But – and let’s be brutally frank here – you’re not going to develop a problem from 20 minutes walking around Ai’s installation.

That said, the Tate Modern has cited “Health and Safety” and roped off the exhibit. You will now not be able to experience it as the artist intended.

What did the artist intend?

In the documentary, Ai very gently mentions the Cultural Revolution and how, in the imagery of the time, Chairman Mao was always represented as the sun while the people were presented as sunflowers.

I think he intended for the sunflower seeds to slowly grind and corrode. Our enjoyment in walking and playing on the seeds comes at the expense of the exhibit itself. The art is about the real outrage of tyranny; that those in power enjoy themselves at the expense of the people they claim to represent.

Porcelain is very hard. The grinding will be slow and gradual, removing only a thin layer at a time.

The original art made us all participants in that process of exploitation.

Instead, with visitors now restrained from the exhibit by subtle ropes stronger than steel, the installation has taken on a whole new meaning; now much closer in context to modern-day Britain.

The seeds are treated like explosive toxic waste. Visitors are permitted- very carefully – to touch some seeds being presented in a bucket by Tate staff.

And so a message about exploitation becomes a message about the terror of risk. Instead of the people being ground down through hardship, they are protected so well that they are incapable of fulfilling their purpose.

I appreciate that some societies have become perpetually paranoid and terrified of the unknown. That risk is to be avoided at all costs.

However, in pursuing the objective of removing all hazards from life, Health and Safety also removes all its pleasure and excitement and innovation.

Pity future generations of children who will not be allowed to run around and play. We are teaching them well. Take no risks. Do nothing out of the ordinary. Be a perfect citizen. We will not invent. We will not imagine.

Life will become like a bed of porcelain sunflower seeds. Up close it is tactile, exciting and stimulating but – behind iron bars – it looks as cold, dull and uninteresting as a layer of gravel.