Yes. Current version of UN ECE Regulation 10 (Revision 6) allows Outdoor Test Site (OTS) and Open Area Test Site Test Site (OATS) as an alternative measuring location. They are alternatives to absorber lined shielded enclosure (ALSE). OTS is an alternative test site for testing vehicles, OATS is an alternative test site for testing electronic sub assemblies or components. But they are not alternative for all of the tests listed in the regulation.
For vehicle emissions and immunity tests OTS is allowed. Requirements of OTS are given on page 8 of UN ECE R10 Rev.6::
“Outdoor Test Site (OTS)” measurement site similar to an open area test site as specified in CISPR 16, however a ground plane is not required and there are dimensional changes.
On page 64 of UN ECE R10 Rev.6, OTS is defined as alternative measuring location:
As an alternative to the requirements of CISPR 12 for vehicles of category L, the test surface may be any location that fulfils the conditions shown in the Figure of the appendix to this annex. In this case the measuring equipment shall lie outside the part shown in Figure 1 of Appendix 1 to this annex.
Absorber lined shielded enclosures (ALSE) and outdoor test site (OTS) may be used. An ALSE has the advantage of all all-weather testing, a controlled environment and improved repeatability because of the stable chamber electrical characteristics.
For ESA/component emissions tests OATS is allowed. But for ESA/component RF immunity tests OATS would not be enough since radiated immunity tests requires ALSE or test chamber.
Requirements of OATS are given on page 93 and Annex 7 of ECE R10:
Alternative measuring location As an alternative to an absorber lined shielded enclosure (ALSE) an open area test site (OATS), which complies with the requirements of CISPR 16-1-4 may be used (see Figure 1 of the appendix to this annex).
To ensure that there is no extraneous noise or signal of a magnitude sufficient to affect materially the measurement, measurements shall be taken before or after the main test. In this measurement, the extraneous noise or signal shall be at least 6 dB below the limits of interference given in paragraph 220.127.116.11. of this Regulation, except for intentional narrowband ambient transmissions.
ECE R10 requires both emission and immunity tests and alternative test sites are explained for each test, if available. There is no alternative test site for the radiated immunity tests of ESAs. Thus for radiated immunity of ESAs, ALSE or other test room/chamber specifications apply.
Let us summary on a table:
|EUT||Test Type||Test Site (Recommended)||Alternative Test Site|
|ESA/Component||Radiated Immunity (20MHz-2GHz)||ALSE||–|