1. OICA input on TF1 discussions for GTR-EVS
EVSTF-08-41e
OICA input on TF1 discussions for GTR-EVS

2. Rationale for Option 3 from TF1 discussions for GTR-EVS
Option 3 from TF1 discussions: Postpone water requirements to phase 2 to allow time for research and a wider discussion of water exposure conditions
Rationale for postponing water testing to phase 2 of the GTR-EVS:
It still remains to be proven that water exposure poses a safety risk in EVs today.
No reported field safety failure occurences caused by loss of isolation resistance exist.
The issue is already satisfactorily addressed by existing technology and engineering practice in the automotive industry, see following pages.
There is ongoing research at NHTSA and other contracting parties addressing water exposure in a wider sense (results of these studies are projected not to be available before 2018)

3. Background information:
The current draft GTR-EVS proposes 2 tests to verify that isolation resistance needs to be considered after REESS has experienced significant water exposure:
Flooding test
Washing test
Washing and flooding are representative examples of severe conditions in normal vehicle operation.
The tests are only required by vehicles not equipped with isolation resistance monitoring systems, as these systems are designed to reliably identify and warn the driver if the isolation resistance threshold is effected.
Both of these tests originate from the revoked ISO (2001) but were removed in the current edition of ISO (2011) since they were deemed unnecessary and not motivated by realistic safety concerns.

4. ISO 6469 Electrically propelled road vehicles - Safety specifications
Part 3: Protection of persons against electric shock
The requirements given in this part of ISO 6469 shall be met across the range of environmental and operational conditions for which the electrically propelled vehicle is designed to operate, as specified by the vehicle manufacturer. NOTE See ISO for guidance.
Protection against electric shock shall be composed of
Basic protection measures against direct contact with live parts
Measures for protection under single-failure conditions.
If the minimum isolation resistance requirement cannot be maintained under all operational conditions and over the entire service life, one of the following measures shall be applied:
monitoring of the isolation resistance
double or reinforced insulation

5. ISO 6469 Electrically propelled road vehicles - Safety specifications
Part 3: Protection of persons against electric shock
Protection against electric shock
Basic protection measures
Measures for protection under single-failure conditions
Basic insulation
Barriers, enclosures
Isolation resistance
Potential equalization
Capacitive couplings
De-energization
If the minimum isolation resistance requirement cannot be maintained under all operational conditions and over the entire service life:
double or reinforced insulation
monitoring of the isolation resistance

6. Conclusions from ISO
Isolation resistance is one of several measures for protection against electric shock under single-failure conditions. The concept is that safety is assured in normal operation and under single-failure conditions.
Washing and flooding are just representative examples of severe conditions in normal vehicle operation. Vehicle safety performance shall be fulfilled under all normal operating conditions. Regulatory safety requirements cannot be tested under all normal operating conditions.
Isolation deterioration doesn’t cause an electric shock when other protection methods (basic protection measures and protection under single-failure conditions) are in place.