OSHA Danger Safety Sign: Sign alerts employees and workers to areas where hearing protection is mandatory. Bold hearing protection text is easily read. Affix anywhere hearing protection is a requirement. 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.Plastic Manufactured with 50% Post-Consumer Recycled plastic and is recyclable – code 2. .055" thick polyethylene, matte surface print. Impact resistant with slight flexibility. Rounded corners and 3/16" mounting holes on most sizes, will be adjusted for larger sizes. Service temperature range: -90°F to 168°F.