Written by James C. Smolka, P.E., CFEI, CESCP, ESi
As you read this article, you probably have a power strip under your desk that powers your laptop, your monitor, your cell phone charger, etc. Power strips, which are officially known as relocatable power taps (RPTs), are designed to be used as a multiple outlet extension in the office and in the home. Many RPTs are listed by Underwriter Laboratories Inc. (UL) meeting the requirements of Standard UL 1363. Some RPTs have limited electrical surge protection and electrical noise filtering for sensitive electronic equipment.
When used as designed, RPTs are useful, reliable devices. However, they have been involved in many fires. Often the fires attributed to RPTs are related to the misuse of the RPT. The picture below shows an example of the misuse of an RPT.
Relocatable power taps were designed for use in an area with a high concentration of low-powered loads such as computers, paraphernalia, and audio/ video equipment. RPTs are not intended for use with high load equipment such as refrigerators, coffee pots, copiers, space heaters, microwave ovens, toaster, toaster ovens, hair dryers, and dehumidifiers. Basically, if the electrical device has a large motor or a large heater, then it was not meant to be plugged into an RPT.
According to UL, RPTs are also known as temporary wire taps and are considered temporary extension of an electrical circuit intended for indoor use. The term temporary also refers to how an RPT is physically mounted. The mounting and removal of a RPT is permitted if tools are not used to secure it in place (i.e., a RPT cannot be secured to a work bench, desk, or a wall by bolting or screwing the RPT to a surface.).
RPTs are great for low power devices. However, there are some do’s and don’ts. According to the NFPA 1, Fire Code, and the UL White Book, RPTs:
- Shall be directly connected to a permanently installed receptacle.
- Are not intended to be series connected (daisy chained) to other relocatable power taps or to extension cords.
- Are not intended for use at construction sites and similar locations.
- Are not intended to be permanently secured to building structures, tables, work benches or similar structures.
- Are not intended to be used as a substitute for fixed wiring.
- Shall not have their cords routed through walls, windows, ceilings, floors or similar openings.
The question for legal minds is, is it illegal to misuse an RPT in the work place? In short, yes. There are ways that the misuse of RPTs can be considered illegal.
The first way that the misuse of an RPT causes a legal issue through violation of the OSHA regulations. The installation and use of electrical equipment, OSHA regulation (29 CFR 1910.303(b)(2) states:
“Listed or labeled equipment shall be installed and used in accordance with any instructions included in the listing or labeling.”
Since RPTs are listed devices, the misuse of a RPT in the work place is an OSHA type violation.
The second way that the misuse of an RPT causes a legal issue is NFPA 70, National Electric Code (NEC), Article 110.3(B), which states:
“Listed or labeled equipment shall be installed and used in accordance with any instructions included in the listing or labeling.”
Since most states have adopted the NEC and have made the NEC a legally enforceable standard, not following the NEC results in a non-compliance of a recognized standard.
Note that the OSHA regulations and the NEC use the same language regarding the use and installation of listed devices. The OSHA regulations tell you what you must do, standards, like the ones from the NFPA, tell you how to meet the OSHA regulations.
RPTs are used in almost all office environments. So, take a moment and look around your office. Are your RPTs in good condition? Are your RPTs used as designed? For safety reasons, the proper use of RPTs is not only recommended, it is an OSHA requirement.
