WARNING It is important to follow all Local, State and Federal regulations when entering a confined space. Contact Local, State and Federal agencies for recommendations and special procedures.

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IMPORTANT: Always refer to the federal confined space regulation 29CFR 1910, Subpart J, 1910.146.

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NOTE: This calculator is meant to serve as a general guideline when working in confined spaces. There are many factors that may affect the situation, therefore, it is critical all safety circumstances be considered before working in any confined space and if there is any question, call Allegro for technical assistance (800-622-3530) or consult a professional.

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“Air quality should be tested prior to ventilating a confined space and should be tested continuously during confined space occupancy to ensure a stable atmosphere and worker safety because atmospheric conditions can change rapidly.”

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