Tate Modern worker claims compensation for being too cold

• Bosses didn't take account of disability, tribunal told
• Employers say they acted to address her complaints

Tate Modern was once a power station Photograph: Charles Bowman/Robert Harding/Rex Features

At five storeys high and with more than 300 square metres of floor area, Tate Modern's Turbine Hall is an undeniably tricky place to keep warm.

But, according to one former member of staff at the London gallery, the temperatures in the vast exhibition space were so low that they contributed to a serious deterioration in her health.

Elizabeth Andrews, a gallery supervisor, has launched a claim for compensation against the Tate, saying that the cold, among a series of other factors, meant she became increasingly ill and eventually had to go on long-term sick leave.

On occasions working in the Turbine Hall, where the electricity generators were housed before the former Bankside power station was decommissioned in 1981, she would wear a shirt, jumper and long coat but "I was still cold", Andrews told an employment tribunal yesterday.

Andrews, 40, who has Crohn's disease and is registered disabled, said she was forced against her will to move from the smaller Tate Britain in nearby Pimlico to Tate Modern, and that her bosses failed to take into account her condition when making the decision. Crohn's causes the body's immune system to attack the intestines, causing problems including digestive complaints, back pain and tiredness.

At Tate Modern, the heavy main entrance doors and the many escalators also caused problems, notably making her back seize up, Andrews told the London South employment tribunal in Croydon.

Without any legal representation and supported only by her partner, Andrews told the three-strong tribunal panel that she had joined Tate Britain in 2003 as a gallery assistant, winning promotion to supervisor the following year. Her bosses there were sympathetic to her health problems, for example letting her work part time for a period and buying a special chair for her back.

But in March 2007 Andrews was issued with a written warning for "rude and aggressive behaviour" following a confrontation with a colleague at a party. This meant they found it hard to work together and managers decided one of them should be moved, Andrews said. If both refused one staff member would be sacked, most probably her, she said she was told.

"I was desperately unhappy about the move and thought this might have a detrimental effect on my disability, bearing in mind the reasonable adjustments that were in place at the Tate Britain had not been put in place at the Tate Modern," Andrews said.

"Nevertheless, I thought I would see how it worked, but I was very unhappy about the move."

In testimony punctuated by weeping, which at one point necessitated a 15-minute break, Andrews said that as soon as she began work at Tate Modern in November 2007 "it became clear that it was not suitable for me". She said: "It is a much bigger and colder building than the Tate Britain."

Air conditioning in the CCTV room where, as a gallery supervisor, she spent time monitoring screens, made her back pain worse. She also had to cover for assistants' absences on the gallery floors, including the Turbine Hall, while the hours affected her health and made childcare more difficult, she told the tribunal.

Her health and self-esteem were "badly affected" by the move, and managers refused to let her return to Tate Britain. "At Tate Britain I had status," said Andrews. "I only ever wanted to remain in the job I loved."

The month after she began at the gallery, Andrews went on long-term sick leave, submitting a written grievance saying the transfer had been "extremely detrimental in terms of working time, childcare arrangements and health".

An internal hearing found in her favour, saying conditions were very different at the two sites and her medical condition had not been properly considered during the process of the move. It was agreed that she could return to work at Tate Britain, which she did in March.

The Tate's board of trustees, the respondents in the case, are contesting Andrews's claim for compensation, saying it has been lodged too late.

Andrews's argument is that the way she was treated formed "one continuing act" and thus she was within time.

Richard Hignett, representing the Tate, questioned whether Andrews had properly explored the way Tate Modern could accommodate her condition given that she had only worked 12 shifts there before taking sick leave. He suggested that the gallery had taken all reasonable measures to address her complaints and questioned why she had not raised the issue of her condition during an initial meeting with Tate Modern managers.

The hearing continues.