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When it pertains to temperature limits, no—the Occupational Safety and Health Administration (OSHA) does not have regulations that state specific temperature limits for materials in general, nor for surface temperatures of insulation materials. You simply can't state an absolute temperature limit for every individual situation. The OSHA does consider hot objects as a potential safety hazard and does say that thermal hazards must be investigated for methods to protect workers. The first method is to prevent access to the hot objects. (Be sure to read Use of Insulating Coatings for Hazard Protection.) If that is not feasible, then personnel protective equipment must be provided.
For reference, OSHA has a letter on its website dated January 27, 2009 that states that OSHA does not have a specific standard nor guidelines as to what temperature should metal pipe be insulated to avoid burning of the skin on contact. In this letter, OSHA refers to ASTM C1055 for more detailed guidance on temperature limits. OSHA does have regulations regarding hot steam pipes, and has regulations about insulating them, but this would be well above the temperature limits of typical thermal barrier (insulation) coatings. I am not aware of any other OSHA regulations that are specific to insulation coatings.