What is the horizontal and vertical measurement zone from the top of the bathtub rim where lighting track cannot be installed?

The proper measurement zone from the top of the bathtub rim, where lighting track cannot be installed, is specified as 3 feet horizontally and 8 feet vertically. This regulation is designed to ensure safety in the installation of electrical equipment in proximity to water sources, especially in areas such as bathrooms where bathing appliances may create a risk of electrical shock.

The horizontal measurement of 3 feet ensures that any potential hazards from the moisture and splashes associated with the use of a bathtub are adequately mitigated. The vertical limit of 8 feet provides a reasonable height at which moisture may still be present in the air, thereby minimizing the risk of electrical equipment interactions with water.

Adhering to these specific distances helps in preventing accidents and maintaining a safe environment for users of the bathtub. This guideline is critical for electricians and builders to follow when planning lighting installations in wet environments.