Nancy Pearce

Wind turbines as confined spaces

Blog Post created by Nancy Pearce Employee on Feb 20, 2013
Windenergy_confined
Photo: www.OSHA.gov
http://www.nfpa.orgTypically we think of climbing down into tanks, vaults or manholes for confined space entries.  Most would not think of wind turbines as having confined spaces. 

Large enough to enter and perform work, restricted means of entry or egress and not designed for continuous human occupancy…. Wind turbines clearly have components that meet the definition of a confined space AND they have potential hazards. 

With the push towards green energy, wind turbine installations are increasing rapidly.  In 2012 wind energy became the number one new energy source, with over 45,000 wind turbine installations currently in the U.S., according to AWEA (American Wind Energy Association).    

 

Windenergy_pg
Photo: www.OSHA.gov
While green technology may be good for the environment, it is not without hazards to the workers who install and maintain the technology.   As OSHA indicates on their Green Job Hazards webpage, “Green jobs are not necessarily safe jobs”.

Hazards for workers in wind turbines include falls, electrical, mechanical, fire, and confined space hazards. Both OSHA and AWEA have pointed out the need for confined space training of wind turbine workers.   Confined spaces exist during construction and after installation of the turbines.  There are four main components that may be considered confined spaces; the tower (vertical support), the nacelle (the housing that contains the electrical components) the hub (hub attaches to nacelle) and the blades (attach to hub).  During construction of the turbine workers may need to enter sections of the tower, nacelle, hub or blades to finish seams, grind, paint, etc.    When fully installed, workers need to climb up the tower to reach the narrow, restricted spaces of the nacelle, hub and blades for maintenance, inspection and repairs.  Electrical hazards have been the source of a number of fatalities and fires in wind turbines within the confined spaces.   An electrical incident or spark that occurs in the nacelle can quickly engulf a worker whose only way to exit the space is to descend a several hundred foot ladder or to climb on the roof of the nacelle. Some nacelles are made with polystyrene type foam which is extremely flammable and adds to the fire risk.  Nitrogen used in the accumulator, off-gassing of construction materials, poor ventilation and sources such as decomposing birds or rodents, can create a hazardous atmosphere.  And if something goes wrong inside a wind turbine, the challenges to rescue are significant.     

The National Fire Protection Association is developing a Best Practices Document for confined space entry. This document will address gaps in existing standards and will be more prescriptive in describing things like how to identify potentially toxic atmospheres and select the proper gas monitor for entry and how to include the evaluation of adjacent spaces into your confined space entry program.    This is a document that is looking to go beyond the minimum standards and will provide those looking to develop a “gold star” confined space entry program with the information they need to do so.  Please email me at npearce@nfpa.org for further information and/or leave a comment below for discussion.  I look forward to hearing from you!

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