The U.S. Department of Labor (“DOL”) is focusing on time that employees spend changing clothes and protective safety equipment (“donning” and “doffing”) and whether such time is compensable work time. Under Section 3(o) of the Fair Labor Standards Act (“FLSA”), 29 U.S.C. § 203(o), the time spent “changing clothes or washing at the beginning or end of each workday” is excluded from compensable time under the FLSA if the time is excluded from compensable time pursuant to the express terms of, or custom and practice under, a collective bargaining agreement. The DOL’s recent Administrative Interpretation (No. 2010-2) sets new compensation rules for donning and doffing activities by analyzing the meaning of “clothes” under Section 3(o) vis-à-vis its legislative history and case law. The Interpretation states, “Based on its statutory language and legislative history, it is the Administrator’s interpretation that the § 203(o) exemption does not extend to protective equipment worn by employees that is required by law, by the employer, or due to the nature of the job.” In addition, the Interpretation concludes that clothes changing that is non-compensable under Section 3(o) may nevertheless be deemed compensable work time if it is a “principal activity,” and, where that is the case, subsequent activities, including walking and waiting, are also compensable work time. Notably, this conclusion is directly contrary to the DOL’s 2007 opinion letter that stated that Section 3(o) clothes-changing activities cannot be principal activities. Finally, the DOL’s Interpretation notes that, although Section 3(o) pertains to employees covered by collective bargaining agreements, its analysis is instructive for all employers. Whether specific donning and doffing activity is a “principal activity” and compensable should be analyzed carefully to avoid wage liability under the FLSA.