The Lenbachhaus Museum in Munich is confronting an unprecedented conservation challenge as it displays American artist Dan Flavin's monumental light installation "For Ksenija" in the Kunstbau gallery. The museum faces a critical dilemma: the specific fluorescent tubes required for the artwork are no longer available for purchase due to environmental regulations, threatening the future of one of the most significant minimal art installations in Germany.

Flavin's light artwork was specially created in 1994 for the opening of the Kunstbau, a 110-meter-long underground gallery space. The installation features four rows of fluorescent tubes in green, blue, yellow, and pink that follow the gently curved length of the space at approximately six meters height. The effect is described as almost magical, with colors and perspectives changing with every step visitors take through the gallery.

The timing of this tenth presentation since 1994 carries additional significance, coming just two weeks after the death of Kunstbau architect Uwe Kiessler. The light-on-architecture artwork now serves as a tribute to the late architect, highlighting the intricate relationship between Flavin's minimal art and the architectural space it inhabits.

Lenbachhaus curator Johannes Stanislaus explained the technical specifications of the installation: "The Kunstbau is 110 meters long. A fluorescent tube measures one meter twenty. They are installed starting at the joint and run the entire length. Three light rails are interrupted by the rotunda." The installation required approximately 300 tubes, which two museum staff members carefully installed over the course of a week using lift trucks.

The conservation challenge stems from Flavin's artistic philosophy of using commercially available objects that were standard in the 1990s. Both the mounting fixtures and the tubes themselves are products from that era that can no longer be purchased in their original specifications. "They are stored in our depot and we have been very fortunate that for every presentation of this work so far, we have been able to use new, unused fluorescent tubes," Stanislaus noted.

Restorer Isabel Gebhardt detailed the technical complexity of the fluorescent tube technology: "In this fluorescent tube is a gas mixture. Among other things, mercury vapor is contained. And when the current flows, this gas is ionized, that is, activated, and ultraviolet radiation is generated." The composition of the coating layer determines the different colors of the tubes, representing an older technology that has been largely phased out.

The environmental regulations that have eliminated these tubes from the market are primarily related to their energy consumption and mercury content. Anyone who has fluorescent tubes at home knows that the old versions have not been available for purchase for several years due to EU directives aimed at reducing energy consumption and eliminating mercury-containing products.

The museum's predicament extends beyond simple replacement issues. Any modification to the installation, such as switching to LED technology, would require approval from Dan Flavin's estate representatives in New York, even 30 years after the artist's death in 1996. This same conservation challenge affects works by other deceased light artists including François Morellet, Keith Sonnier, and Mario Merz.

When asked about recommendations for when the depot supplies run out, Gebhardt acknowledged the severity of the situation: "Purchasing more is no longer an option. There are EU regulations that have significantly changed the situation. There are hardly any fluorescent tubes left on the market and we are now really actively looking at: Is our supply sufficient? If so, until when? Do we need to stock up further? And this is actually a dilemma that museums and institutions are currently facing."

The broader implications of this conservation crisis highlight the unique challenges facing contemporary art institutions. Unlike traditional artworks made from stable materials, light-based installations depend on industrial components that may become obsolete due to technological advancement or regulatory changes. Museums worldwide are grappling with similar issues as they attempt to preserve the artistic integrity of works that were created using materials no longer in production.

This situation at the Lenbachhaus represents a microcosm of the larger questions surrounding the conservation of contemporary art in an era of rapid technological change and increasing environmental consciousness. The museum continues to monitor its remaining supply while exploring potential solutions that would maintain the artistic integrity of Flavin's vision while adapting to the realities of modern conservation challenges.