What Does The Three Ts of Object at Height Safety Mean?
The three Ts of object-at-height safety, also referred to as “the three Ts of dropped-object safety,” are “trapping,” “tethering,” and “topping.” These concepts are the primary hazard controls used to prevent workplace injuries from falling objects.
Trapping refers to the installation of an attachment point onto a tool so the tool is capable of being securely tethered to an anchoring point. Tethering refers to the securing of a tool to an anchoring point via a lanyard. Finally, topping refers to the use of a secure container that tools or other objects will not fall from during work or transportation. The term “topping” is used with reference to the common practice of transporting tools to workers at-height via a bucket or similar container, a practice which is unsafe unless the bucket is enclosed by a secure top.
Safeopedia Explains The Three Ts of Object at Height Safety
The concept of the three Ts is just one element of larger efforts to prevent injuries due to objects falling from height. According to the U.S. Bureau of Labor Statistics (BLS), more than 42,000 workplace injuries due to falling objects are reported each year. In 2015, the BLS recorded 519 deaths due to workers being struck by falling objects or equipment, making it the third most common form of workplace fatality in the U.S.
The concept of the three Ts promotes the idea of trapping because most tools do not come with attachment points suitable for affixing a lanyard tool. Purpose-built trapping devices allow attachment points to be retrofitted securely onto tools, and similar equipment can be used to safely install anchoring points for the tools to be tethered to.
Tethering is the aspect of falling-object safety that most people are familiar with. Tethering a tool to an appropriate anchor point prevents it from falling an unsafe distance should it be dropped or begin to fall from height. There are multiple types of tether available, but the primary safety feature of them all is to limit the distance an object can fall.
Topping is emphasized as a safety principle due to the risk associated with moving tools in containers that are not securely closed at the top. Topped containers include tool pouches and hoist buckets that have been securely closed at the top via a zipper, locking mechanism, or other method. If a container cannot be closed at the top, the tools within it must be securely tethered to the container itself.