This site has an excellent collection of safety resources for both elementary and secondary.
Here’s a description of the resource from the site:
Lab safety is of paramount importance. Whether students are making sense of phenomena or designing solutions in a classroom, laboratory, or community setting, educators need to be proactive in ensuring everyone’s safety. In partnership with Flinn Scientific and their safety experts, CSSS updated a series of resource documents to support effective safety policies in elementary schools, STEM labs, and secondary science spaces. These newly-updated resources answer many of the questions that local school boards, supervisors, educators, and parents have about safety. The manuals provide easily-accessible, concise safety guidance on topics such as safe operating procedures for STEM equipment, accident prevention, chemical waste management, and personal protective equipment.
Link to resource:
http://cosss.org/Safety-Resources