How to Install EMS Marker Balls for Fiber - and Why Locating Depth Matters
By Victor | Mocbo · Blog Article · Focus: marker ball installation
A marker ball only pays off if it is placed where your crew can find it again in five years. This guide covers the install workflow, the APWA color rule, and why a 1.5 m read depth is enough for almost every fiber and telecom route.
The single most common install mistake is using the wrong color. Under the APWA Uniform Color Code, telecom and fiber facilities are marked orange at 101.4 kHz . Power is red (169.8 kHz ), water is blue (145.7 kHz ), sewer is green (121.6 kHz ), gas is yellow (83.0 kHz ).
| Utility | Color | Frequency | Typical marker spots |
|---|---|---|---|
| Telecom / Fiber | Orange | 101.4 kHz | Splices, bends, handholes, DAS nodes |
| Electric | Red | 169.8 kHz | Conduits, transformers |
| Potable water | Blue | 145.7 kHz | Mains, valves |
| Sewer | Green | 121.6 kHz | Force mains, manholes |
Match the color to the facility, not to the trench. An orange ball on a fiber route is read as "telecom" by every locator that passes over it.
| Step | What to do | Why it matters |
|---|---|---|
| 1. Place above the asset | Drop the ball directly over the splice, bend, or valve you want to mark | Keeps the marked point and the physical asset aligned |
| 2. Keep it in the trench zone | Bury within the conduit or cable envelope, not off to the side | Avoids false locates from adjacent facilities |
| 3. Let the coil self-level | Do not force orientation; the water/glycol fill levels it | Stable, repeatable signal on every read |
| 4. Mark every key point | Splices, bends, laterals, handholes | More marks = faster, safer future locates |
| 5. Log the frequency | Note 101.4 kHz / orange on the as-built record | Closes the loop with one-call and locate crews |
Depth rating is the distance from the surface to the ball at which a standard locator still gets a clean read. The Mocbo MB22 is rated for a readable depth of up to 1.5 m (5 ft). That covers the vast majority of North American fiber and telecom bury depths, including direct-buried FTTx drops and conduit zones.
The 1.5 m rating was confirmed during 3M Dynatel 2573 compatibility verification (Test Report P12-21-026-01, 11/11 checks). In practice, deeper placements still return a signal but with reduced certainty - so keep the ball in the upper portion of the trench whenever the design allows.
You do not need new equipment. Because MB22 is tuned to 101.4 kHz it is detected by the same locators your crews already carry - 3M Dynatel, Tempo Marker-Mate, and Radiodetection. The verification against the Dynatel 2573 means the read behaves like the brand-name telecom markers your team already trusts.
| Specification | MB22 value |
|---|---|
| Frequency | 101.4 kHz ±2.5 kHz (orange / telecom) |
| Ball diameter | 110 mm |
| Readable depth | Up to 1.5 m (5 ft) |
| Coil | Self-leveling, water/glycol filled |
| Ingress protection | IP68 |
| Service life | 50 years |
| Locator compatibility | 3M Dynatel 2573 / Tempo / Radiodetection |
Mocbo supplies MB22 in the full APWA color set with a 1.5 m read depth and 3M Dynatel 2573 verification. Email victor@mocbo.com for sample pricing and the test report.
How deep should I bury a marker ball?
Place the ball directly above the asset you want to mark, typically within the trench or conduit zone. The Mocbo MB22 is locatable from the surface at depths up to 1.5 m, so normal bury depths for fiber and telecom are well within range.
Which color and frequency for fiber?
Fiber and telecom use the orange marker at 101.4 kHz under the APWA color code. Using the wrong color risks confusing the facility type during a locate.
Do I need a special locator for Mocbo MB22?
No. MB22 is tuned to 101.4 kHz and was verified with a 3M Dynatel 2573 locator (11/11 checks, Test Report P12-21-026-01). Any locator that reads the 101.4 kHz telecom band will detect it.
How many marker balls per route?
Mark every point that matters for future locates: splices, bends, handholes, valve sites, and lateral take-offs. More marks mean faster, safer locates later.
Does Mocbo also supply Safety Clothing fabric?
Mocbo's core production is passive EMS marker balls (MB22) for telecom, utility, and distribution customers. Our ISO 9001 / 45001 / 14001 quality system also supports industrial textile sourcing for field crews, including Safety Clothing fabric.