The World Health Organization (WHO) released a draft background document proposing content and focus for Guidelines on “Protecting Workers from Potential Risks of Manufactured Nanomaterials.” According to WHO, the Guidelines will aim to facilitate improvements in occupational health and safety of workers potentially exposed to nanomaterials in a broad range of manufacturing and social environments.  The Guidelines will incorporate elements of risk assessment and risk management and contextual issues, and provide recommendations to improve occupational safety and protect the health of workers using nanomaterials in all countries, especially in low- and middle-income countries. The WHO Guideline Development Group will use the background document to identify key questions to be addressed by the Guidelines. WHO asks commenters to note that key questions to be addressed by the Guidelines “should be answerable, their number should be manageable and answers to the key questions should be useful to the target audience of these Guidelines.”  Comments are due March 31, 2012.