Which packaging type is associated with potentially life-endangering amounts of radiation?

Steel casks are associated with potentially life-endangering amounts of radiation because they are specially designed and constructed to safely contain and transport radioactive materials. These casks are robust and often heavily shielded to protect against radiation exposure during transit, preventing any leakage of radioactive substances. The use of steel casks is common in the nuclear industry for transporting spent nuclear fuel or highly radioactive waste, as they must meet strict regulatory standards for safety and contain the hazardous materials effectively. Other packaging types, while they may have some level of protection, do not provide the same degree of shielding and security needed for handling such dangerous levels of radiation.