A 32-year-old Spanish worker was killed on 29 March when he plunged from a wind turbine in East Renfrewshire, Scotland.
The turbine, which is part of Scottish Power Renewables' (SPR) 539MW Whitelee onshore windfarm, was under maintenance by GE at the time of the incident.
The fatality came just a fortnight after Portuguese worker Antonio Linares, 37, fell to his death inside a turbine that was being built at SPR's Kilgallioch onshore windfarm in South Ayrshire.
The victim was employed by Gamesa, a wind turbine manufacturer which, along with Police Scotland and the Health and Safety Executive (HSE), is investigating what happened.
Unite regional co-ordinating officer Steve Dillon said: "In recent years there have been far too many deaths and injuries involving windfarms. These installations are usually in remote locations and there is a concern that these tragedies have not received the same focus if they had occurred in more populous areas.
"Swift action needs to be taken to improve workers' safety and wellbeing and to understand how these incidents occurred. The Health and Safety Executive needs to bring together all concerned to learn the lessons and improve safety and welfare in this sector."
The deputy chief executive of trade association RenewableUK, Maf Smith, said in a statement: "All wind turbine manufacturers, installers and owners regard health, safety and wellbeing as the very highest priorities, and work diligently to ensure that they meet extremely rigorous health and safety standards.
"In these rare but tragic circumstances it's important to ensure that our industry learns from incidents and implements any lessons promptly. A full investigation is currently under way.
"The wind industry works closely with the HSE to ensure that the highest standards are maintained and constantly improved on. We understand that the organisations involved are working with the HSE to establish the exact circumstances of the incident and ensure that the appropriate action is taken."