DANGER CONFINED SPACE AUTHORIZED PERSONNEL ONLY CONFINED SPACE - Confined space sign helps regulate and prevent unauthorized entry. Use of this sign helps cordon areas that are for authorized personnel only. Sign carries a clear message and is sure to get attention. Traditional OSHA-style signs, tags and labels are the most widely recognized design format in the industry. Danger header indicates a hazardous situation that, if not avoided, will result in death or serious injury.