Seems way lower than any other result I've had in the past. I'd have expected a CO around 0.5-1% and HC 100-200 ppm. I think it may have been sniffing fresh air (or what passes for fresh air in a MOT test station).
1st test I got CO 7.083% (limit 3.5%) HC 312ppm
The Lambda sensor had failed. I fitted a 100K mile / 10 year old one from a scrap car and hoovered the Apexi twin cone filter.
last year was 0.881% CO, 175ppm HC