What type of equipment is designed with a means of sealing or locking to prevent access to live parts?

The correct choice indicates equipment designed specifically with a means of sealing or locking to prevent access to live parts is referred to as "Sealable Equipment." This type of equipment is engineered to ensure safety by limiting access to hazardous components, thereby reducing the risk of electrical shock or contact with live electrical parts.

Sealable equipment must have features such as covers, panels, or locks that can only be removed or opened using special tools or procedures, which further enhances the safety of personnel working in or around electrical installations. This is particularly crucial in environments where maintenance tasks are performed, ensuring accidental contact with energized components is minimized.

The other options do not align with this specific definition as directly. Lockable equipment implies a locking mechanism is present, but it doesn't specifically emphasize sealing or preventative features in the way that sealable equipment does. Enclosed equipment suggests that electrical components are housed within a structure but does not necessarily indicate they are sealed or locked from access. Secured equipment, while it may imply protection or safety features, does not specifically reference sealed access to live parts as clearly as sealable equipment does.