There’s a quiet tension every time we load up for a perforation well. Even with years in the wireline business, that moment before arming the gun still gets my full attention. Especially when we’re dealing with RF Safe Control Fire Assemblies in a live stage wireline and perforating setup.
We were working a horizontal wireline job on a tight frac schedule—multi-stage, multi-gun run. The logging cable was prepped, the wireline truck staged, and the gun string had already been loaded and checked. But we weren’t armed yet. Not until we followed every step in the RF-safe process.
And that process? It’s the reason we walked away from that job with perfect execution and zero safety incidents.
It Starts with the VeriFire Panel
Before even thinking about arming a perforating gun, we ran the switch check with the VeriFire panel. This battery-powered tool confirms proper function of the Control Fire Assembly (CFA)—specifically the ControlFire switch inside.
One rule I drill into my wireline courses:
Never operate the VeriFire panel while it’s plugged into the charger. That RF signal is real, and it can detonate a switch if you’re careless.
We tested every switch through the tandem ports. Clean results. No anomalies. Now it was time for the arming sequence.
The CFA Arming Procedure—The Right Way
This is where discipline separates real wireline service providers from the ones who just “get by.”
We connected the CFA to the firing head as per API RP 67, with the detonator still safely inside the explosive safety tube. The color-coded wires were connected with precision:
- White wire: from the upper gun or firing head
- Black wire: ground
- Blue wire: to the tandem sub (lower gun)
Then we turned the shunt connector from “SHUNT” to “ARM” and verified continuity with a certified OHM meter. Only then did we remove the detonator from the safety tube, place it into the black block, align it with the detonating cord, and insert the full assembly into the perforating gun body.
We ensured no wires were pinched. Applied thread lock. Secured the port plug. Checked and double-checked the orientation of the det cap.
This might sound like overkill to some—but when you’re managing perforating gun oil and gas operations, there’s no such thing as too careful. One slip-up here, and you’re not just talking about missed depth—you’re talking about risk to personnel, equipment, and well integrity.
The Golden Rule: One Gun Armed at a Time
Another policy we stick to no matter what:
Only one armed perforating gun is allowed on surface at any given time.
Does it slow us down? Maybe.
Does it save lives? Absolutely.
The wireline oilfield is unpredictable enough. By limiting exposure, we reduce the risk from static discharge, RF interference, and operator error. And in today’s wireline services oil and gas environment, where crews are asked to do more with less, these safety protocols keep the job—and everyone on site—intact.
What Every Wireline Tech Should Know
If you’re coming up in this field—learning the ropes through wireline well logging, cased hole logging, or running a perforation services crew—this process needs to be second nature.
Whether you’re using pump down perforating methods, prepping a perf gun, or assembling a control fire string for a stage frac, knowing how to safely arm and test an RF-safe system is mission-critical.
Wireline technologies evolve fast, but the fundamentals stay the same: discipline, documentation, and doing it the right way every time.