Technical Safety BC (TSBC) has completed its investigation of the DC fast-charging incident in Hope, British Columbia, that occurred in August 2024, concluding that the charger (not the CCS1-to-NACS adapter) caused the incident.

The TSBC’s final report completely clears the A2Z EV’s CCS1-to-NACS adapter and assigns responsibility for the short circuit to the FreeWire Boost Charger.

The Issue

The incident, as captured on the video linked above, occurred when a Tesla electric car was connected to a battery-integrated FreeWire Boost Charger using a CCS1-to-NACS charging adapter manufactured by A2Z EV.

Within seconds of initiating the charging session, an arc-flash and explosion from the charging adapter knocked the user to the ground, leaving them with minor scrapes and abrasions.

The incident resulted in burn marks on the vehicle, complete destruction of the CCS1-to-NACS charger adapter, damage to the charging cable, and damage to the charger’s internal components.

The Cause

Initially, some thought that maybe the CCS1-to-NACS adapter might be to blame. However, the TSBC’s investigation revealed that responsibility for the DC fast-charging incident falls on the charger, which had a short circuit in a battery module:

“A short circuit in a battery module occurred in the charger resulting in abnormal voltage being sent through the charger adapter. Subsequently the charger adapter experienced an internal arc fault and explosion which damaged the adapter and vehicle.”

A2Z EV’s technical statement on the incident explains what happened in stages: a short circuit inside the charger allowed voltage to appear on the protective-earth (ground) circuit, which should usually not happen or be interrupted by the charger. The current flowing through the ground conductor caused heat buildup inside the adapter and an eventual arc-flash:

“According to TSBC’s official report, the charger within the charging station experienced an internal short circuit that allowed voltage to appear on the protective-earth (ground) circuit. This extremely rare and abnormal condition travelled through the charger cable within the charging station into the connected adapter, which led to an arc-flash during the startup sequence.

In a normal EV charging setup, no current should flow continuously through the ground conductor — it exists only as a safety path in case of a fault. In the Hope incident, the charger within the charging station developed an internal short that energized this ground line, allowing continuous current to flow where none should. This abnormal condition caused heat buildup and an eventual arc-flash. The adapter simply became part of the fault path; it did not cause or sustain the current. Under safety standards, the charging station should have instantly detected and interrupted that fault.”

The adapter itself was not safety-certified, but there was no finalized approval standard at the time. Prior to the DC fast-charging incident, the vehicle’s owners had used the adapter approximately 50 times without any issues. By the way, A2Z EV announced that its CCS1-to-NACS adapters received UL2252/CSA-C22.2 safety certification back in September 2025 (an industry first).

A2Z EV concludes:

“Our own inspection found no manufacturing or insulation defect in the connected A2Z EV adapter. The damage observed was consistent with exposure to an external ground fault originating from the charging station. The adapter became a secondary path for current once the charger’s internal fault energized the ground circuit. Under normal operating conditions, this event would never have occurred.”

The Future

EV charging incidents are relatively rare. Hopefully, the one from Hope, British Columbia, will prompt DC fast-charging station manufacturers to double-check their safety measures.

FreeWire Technologies is no longer in business. According to previous reports, its assets, including its intellectual property and engineering team, were acquired by a new owner, who operates under the OptiGrid name with support from Orange EV.

The case is also a lesson for us all, as sometimes even UL-certified equipment might fail, while adapters are not necessarily the issue.