Visitors to an Austrian museum transcend the exhibition space on a steep black staircase constructed from layers of net by design collective Numen/For Use (+ slideshow).

Numen/For Use designed the traversable installation, titled Net Linz, for the OK Center for Contemporary Art in Linz, Austria.

The Austrian design collective constructed the piece, which sees visitors "flying" several stories above the floor, in the gallery's narrow stairwell.

"The input was that the installation has to enable alternative staircase i.e. a structural appendix to the existing hardware of the building," said Numen/For Use co-founder Nikola Radeljkovic.

"The project is an evolution of previous Net installations, specially designed for the space given to us at OK house in Linz," he added.

The woven structure gently sways as climbers ascend the ravine-like space, bordered on one side by a raw concrete wall and on the other by the gallery's metal-framed staircase.

Numen/For Use have produced a number of installations using nets, but always on a horizontal plane. For this vertical construction the designers had to experiment with new types of tensioning to make the staircase safe for visitors.

"When you have people 'flying' eight metres above the floor and other visitors, you have to take safety seriously," said the designer, whose studio also created a web-like installation for the Belgian gallery Z33.

Applying the same principles to the net construction as a standard staircase, the designers constructed a five-metre-long 1:4 scale-model to test how the tension would be distributed before creating the piece.

"Since the physics of the structure work totally different in horizontal and vertical 'modes' we had to test the idea in larger and larger and larger models," said Radeljkovic.

The final structure was made from four layers of netting, suspended from the ceiling of the stairwell and tensioned by a series of weighted sand-bags.

Two columns of netting are tacked together, giving the piece a curved, sinuous outline. Portholes in the walls of the net-work connect the two channels allowing visitors to pick their route to the top.

"Since walking is rather uncomfortable because of the hardness of the net, we were concerned how people would react," said Radeljkovic.

"But the response was more than satisfactory – some even went up and down for hours. It's like this thrill of exposure to height and wobbliness suppressed the physical discomfort," he added.

Net Linz was on show at the OK Centre for Contemporary Art in Linz until 19 October.