Final answer:
Radon and asbestos are two commonly found invisible safety hazards in older structures that can pose serious health risks.
Step-by-step explanation:
The two commonly found invisible safety hazards within older structures are radon and asbestos.
Radon is a radioactive gas that is naturally present in small amounts in soils and minerals. Its accumulation in well-insulated, tightly sealed buildings, however, constitutes a health hazard, primarily lung cancer.
Asbestos is a mineral fiber that was commonly used in insulation, flooring, and other building materials. Exposure to asbestos can cause serious health problems, including lung diseases and cancer.