The Occupational Safety and Health Administration plans to propose a new rule requiring employers to protect employees exposed to high temperatures at work. This federal government regulation is the first of its kind to provide protection from heat on the job. As the summer months arrive and heat records rise, employers would do well to examine OSHA’s proposal, and to understand the legal pitfalls facing employers under the National Labor Relations Act (NLRA) and the Labor Management Relations Act (LMRA), should employees complain about or walk off the job due to excessive heat in the workplace.