In 2007, NIOSH created the Science Blog as its first social media channel. The blog has more than 22,000 subscribers. The purpose of the evaluation was to identify the blog community of readers, its use as a two-way conversation channel and its effectiveness as an information resource. Seventy-five readers randomly participated in an online survey from July 2009 to September 2009 to evaluate the Science Blog. Responses indicated that the NIOSH Science Blog was a valued social media resource. Sixty percent of participants planned to continue using the blog in the next 6 months. A significant proportion of readers reported that they would make changes in the workplace based on information obtained from the Science Blog. The NIOSH Science Blog provides is a useful communication channel to provide workplace safety and health information and expand the Institute's reach to new consumers. Copyright © 2011 Wiley-Liss, Inc.