Article 525: Carnivals, Circuses, Fairs, and Similar Events

 

By Mike Holt for EC&M Magazine

 

Keep fun events safe, by correctly applying Article 525.

If you do electrical work with temporary events, you need to understand Article 525. But what if you don’t do such work—is it worthwhile to understand Article 525? Yes.

Maybe you work in the maintenance department of a widget factory. There may be days when you jokingly remark, “This place is a real circus,” but that hardly qualifies it for Article 525. Or maybe you are a contractor, but your firm does industrial work only. Can Article 525 possibly matter to you? Yes.

One way it can matter is this. If you review Article 525, you see that it addresses such things as equipment protection, wiring methods, and GFCIs. So Article 525 is an excellent text for seeing how some key NEC concepts work together.

A more compelling reason involves the fact that you are not a layperson in electrical matters. Thus, situations will probably arise where lay people will look to you for guidance, even if you do not directly do Article 525 work. Lay people don’t know Article 525 from Article 430—anyone “electrical” must be an “expert” on all electrical things.

You may, for example, be “volunteered” to a committee that oversees an event for your employer, church, civic group, alumni association, or school. An understanding of Article 525 allows you to provide good advice. You might be the point person, project manager, or resident expert representing your group.

Many electrical engineers and electricians make a point of looking for Code violations both on the job and off. This leads us to the most compelling reason of all for understanding Article 525: You may take your child or grandchild to a circus or other event. With your knowledge of Article 525, you can do a visual inspection of rides or other attractions that could endanger the child. Imagine the alternative—you were there, but didn’t see the Code violation that caused a tragedy. Some of these violations are very easy to spot—but you need to know what they are. We’ll discuss Article 525 from the viewpoint of the installer, but will also identify some easy inspection points along the way.

What’s inside

Article 525 covers the installation of portable wiring and equipment for carnivals, circuses, exhibitions, fairs, traveling attractions, and similar functions [525.1]. At first glance, a couple of questions arise. “Aren’t these just like assembly occupancies? Why do we need Article 525, if Article 518 covers the same thing?”

Yes, these locations are similar to assembly occupancies [Article 518]. But they are not the same. In fact, there are two big differences:

• Article 525 applications are temporary, while Article 518 occupancies are not.
• Article 518 does not cover amusement rides and attractions, while Article 525 does.

You may want to compare these two Articles to see if you can spot other similarities and differences between them. Doing so will help you understand both Articles better.

Another Article that is often mistakenly applied to these events is Article 590, which governs temporary installations.  While carnivals, fairs and similar events are indeed temporary in nature, they also have a distinct safety hazard associated with them--the general public, particularly children, will be in intimate contact with electrical equipment.  Because of this, Article 525 contains requirements that are more stringent than those installations typically found at the job site.

Also, note that Article 525 does not address:

• Audio signal processing equipment. Anyone setting up the sound stage will need to refer to Article 640 [525.3(C)].
• Attractions that utilize water. Anyone installing such things as swimming pools, fountains, dunk the boss, bumper boats, and duck ponds needs to refer to Article 680 [525.3(D)]. If you use electric motors to circulate water in a tank which guests might touch, Article 680 applies. A key provision: 680.21(A)(1) permits a GFCI-protected single locking-type receptacle for a water-pump motor between 5 ft and 10 ft from the water (Figure 525-1).

Overhead Conductor Clearances

If you are that parent or grandparent mentioned earlier, overhead clearance requirements make easy inspection points for you.

Overhead conductors must have a clearance of 15 ft from amusement rides and attractions (except, of course, for the conductors that supply power to the ride or attraction) [525.5(B)].

For overhead conductors installed outside tents and concession areas, the vertical clearance requirements of 225.18 apply [525.5(A)] (Figure 525-2). The minimums are:

• 10 ft above finished grade, sidewalks, platforms, or projections from which they might be accessible to pedestrians for 120V, 120/208V, 120/240V, or 240V circuits.
• 12 ft above residential property and driveways, and those commercial areas not subject to truck traffic for 120V, 120/208V, 120/240V, 240V, 277V, 277/480V, or 480V circuits.
• 18 ft over public streets, alleys, roads, parking areas subject to truck traffic, driveways on other than residential property, and other areas traversed by vehicles (such as those used for cultivation, grazing, forestry, and orchards).

Power sources

Service equipment must not be accessible to unqualified persons, unless the equipment is lockable [525.10(A)]. See the Article 100 definition of “Accessible” as it relates to equipment and service equipment. This is another easy inspection point—also check to see that this equipment is actually locked.

Mount service equipment on solid backing. Many temporary installations fail in this regard—remember that the mounting is a critical safety issue. If the equipment is not of weatherproof construction, install it in a way that protects it from the weather [525.10(B)].

Where multiple services or separately derived systems (or both) supply rides and other structures, are any sources of supply separated by less than 12 ft? If so, bond these to the same grounding electrode (earthing) system [525.11]. The 12-ft separation of structures is simply a nominal value; there is no strong technical reason for this measurement. Having a specific value allows consistent enforcement.

Where electrical equipment or wiring is subject to physical damage, provide it with mechanical protection [525.6]. This requirement applies to the entire installation, not just the service.

Wiring Methods

Flexible cords or cables in compliance with Article 400 must be listed for extra-hard usage. When used outdoors, they must be listed for wet locations and must be sunlight resistant (Figure 525-3). Flexible cords or cables must be continuous without splice or tap between boxes or fittings [525.20] (Figure 525-5), and they can never be used where subject to physical damage [400.8(7)].

You can use single conductor cable in sizes 2 AWG or larger. You can also use open conductors  that are part of a listed  assembly, or you can use open conductors in festoon lighting per Article 225 (Figure 525-4) [525.20(C)].

Do not lay cord connectors on the ground, unless they are listed for wet locations. Connectors placed in audience traffic paths or areas accessible to the public must be guarded (Figure 525-6)—this is another easy inspection point.

A ride or structure must not support wiring for an amusement ride, attraction, tent, or similar structure unless the ride or structure is specifically designed for this purpose.

Two related requirements for rides and structures [525.21]:

1. Each ride and concession must have a fused disconnect switch or circuit breaker within sight and within 6 ft of the operator’s station.
2. Inside tents and concession areas, securely install the wiring for lighting. If the wiring is subject to physical damage, provide mechanical protection. Protect all lamps for general illumination from accidental breakage by a suitable luminaire or lampholder with a guard.

GFCI-Protected Receptacles and Equipment

GFCI protection is not required for receptacles of the locking type [525.23]. You may decide to add an extra margin of safety by installing it. But don’t blindly install GFCI devices everywhere—GFCI protection is not permitted for egress lighting.

GFCI protection is required for all:

• 15A and 20A, 125V nonlocking type receptacles used for disassembly and reassembly of amusement rides and attractions, or readily accessible to the public.
• Equipment readily accessible to the public, if supplied from a 15A or 20A, 120V branch circuit. This rule applies even if the equipment is not cord and plug connected.

You can use listed cord sets incorporating GFCI protection (Figure 525-7). GFCI protection for personnel can be an integral part of the attachment plug, or it can be located in the power-supply cord if it is within 12 in. of the attachment plug.

Grounding and bonding

You must bond the following equipment together, if they are connected to the same power source[525.30]:

• Metal raceways and metal-sheath cables.
• Metal enclosures.
• Metal frames and metal parts of rides, concessions, tents, trailers, trucks, or other equipment that contain or support electrical equipment.

Ground (bond) the metal parts of all electrical equipment to the grounded (neutral) conductor at the service disconnecting means per 250.24(C) (or the separately derived system per 250.30(A)(1)) [525.31].

Someone must verify the continuity of the equipment grounding (bonding) conductor each time anyone connects the portable electrical equipment [525.32]: Verification of the equipment grounding (bonding) conductor is necessary for electrical safety. However, this requirement is vague. It doesn’t specify:

• Who is required or qualified to perform the verification
• What verification means
• Where to record the verification
• How you must verify the grounding (bonding) conductor
• Which circuits you must verify.

To avoid liability problems, talk to your insurer and the AHJ for guidance and their requirements, then get those in writing.

With your knowledge of Article 525, you can prevent tragedies at events that were meant to be fun. You can do this whether you are the installer, inspector, the project manager, an advisor, or a customer.