Which of the following is a method to ensure safety when working at heights?

Using guardrails and safety harnesses is a fundamental method to ensure safety when working at heights. These safety systems provide critical protection against falls, which are one of the leading causes of injuries and fatalities in the construction industry. Guardrails act as a barrier to prevent workers from accidentally falling off elevated surfaces, while safety harnesses, when properly used in conjunction with a secure anchorage point, can stop a fall before serious injury occurs.

Implementing these safety measures significantly reduces the risk of accidents and promotes a safer working environment. By using guardrails and safety harnesses, workers can perform their tasks with greater confidence, knowing that they have layers of protection in place to safeguard against potential falls, which aligns with OSHA regulations designed to protect workers from hazardous conditions.