His call came after it was revealed the Health and Safety Executive (HSE) had made only two visits in five years to check the sites at the centre of the investigation into the Edinburgh outbreak.
The former Chancellor, who is MP for Edinburgh South West, tabled parliamentary questions at Westminster to find out how often HSE inspectors had visited the North British Distillery, pharmaceutical firm Macfarlan Smith and Burton’s Foods in the last five years.
The ministerial reply revealed there had been no visits to the North British Distillery to check for legionella risks in that time, though an assessment of major accident hazards had been carried out on March 15, 2010.
Macfarlan Smith had received a legionella risk inspection on February 4, 2010. And Burton’s Foods was inspected for legionella risk on June 17, 2008.
Mr Darling said: “I’m surprised there have not been more inspections given that this is a known hazard, especially when there have now been more than 90 cases, with sadly two fatalities.
“There are clearly lessons to be learned, not just for Edinburgh, but for the whole country.
“Sadly, legionnaires’ can kill and a lot of people have been put to a lot of distress and some remain very ill.
“HSE needs to completely reconsider its inspection regime.”
The written answer from minister Chris Grayling said: “Inspections are only one tool the HSE have available to help companies meet their legal obligations to control and manage risks in relation to legionella.
“HSE also provides free guidance in addition to ongoing work with water treatment firms and trade bodies.”
The call followed news last week that despite the results of tests coming back investigators were still unable to pinpoint the source of the outbreak.
The incident management team has concluded that the “cluster of cooling towers” located in Wheatfield Road were believed to be responsible. NHS Lothian said that further analysis of the samples was ongoing.
Two of the firms at the centre of the outbreak, chemical firm Macfarlan Smith and North British Distillery, are located on Wheatfield Road.
Both companies, who were criticised over their cleaning regimes, issued statements saying they had confidence in their anti-infection work.
The number of confirmed cases now stands at 47, with 46 suspected. Two people have died, while one person is now being treated in intensive care and a further 17 are on general hospital wards.