Five people are taking legal action over a Legionnaires' disease outbreak which has left two people dead.
The five, who are all understood to have contracted the disease, are seeking answers over what went wrong and have insructed law firm Irwin Mitchell.
Health chiefs investigating the outbreak in Edinburgh today served an improvement notice on the National Museum of Scotland in the capital.
Edinburgh City Council said the notice served on the museum relates to staff training issues and not the operation of cooling towers.
So far there have been 41 confirmed cases and 48 suspected cases in the outbreak in the south-west of the capital.
The first man to die was named as Robert Air, 56, from the Seafield area of the city.
Yesterday evening a second person died after contracting the disease.
The man, who had significant pre-existing underlying health conditions, died in Edinburgh Royal Infirmary.
Irwin Mitchell said they are receiving ongoing inquiries about the outbreak.
Their clients include Terry Holleran, 55, who said he has instructed specialist illness lawyers at the firm to help him find out how the outbreak occurred and what can be done to prevent it from recurring.
He said yesterday: "It has been one of the worst weeks of my life.
"I'm just so angry about the whole thing and want to know what went wrong to cause the outbreak."
Health chiefs said it appeared the outbreak has peaked, with figures remaining static today.
The National Museum of Scotland in Chambers Street, Edinburgh, is the third place to be served with an improvement notice by investigators.
The notice requires the museum to ensure that key staff members are appropriately trained in the management of water systems, which includes overseeing the ongoing monitoring and maintenance regime undertaken by specialist contractors.
A council spokesman said: "The improvement notice relates solely to the training of staff and not to the operation of cooling towers."
The notice does not mean the National Museum of Scotland has been identified as the source of the outbreak. The museum can appeal against it within the next 21 days.
A spokeswoman for National Museums Scotland, which runs the museum, said: "We employ specialist contractors to regularly test, monitor and ensure the safety of our water systems. Tests have confirmed that there are no issues with Legionella in our cooling towers.
"Following a routine inspection by the Health and Safety Executive and the City of Edinburgh Council Environmental Health, both organisations confirmed they are satisfied with our documentation and procedures.
"Environmental Health Officers have now commented on a routine matter and have asked that the staff who appoint and oversee specialist contractors should undertake refresher training."
Two other organisations, pharmaceuticals firm Macfarlan Smith and the North British Distillery, have already been served with improvement notices.
These do not mean any of the cooling towers are the source of the outbreak.
Health Secretary Nicola Sturgeon MSP said: "I would like to take this opportunity to again express my sincere sympathy to the friends and family of the patient who passed away yesterday. My thoughts are with them at this very difficult time.
"This is an extremely sad development. However, it is reassuring that the number of cases involved in the outbreak remains static and this is further evidence that the outbreak has reached its peak."