Should we say H0 or HO?

Whether to use the term HO (letter O) or H0 (zero) is not something that causes many modellers a sleepless night. We are accustomed to both being understood and accepted when written or typed. The fact is that usually when we use the term it is done verbally and as they sound the same when spoken there is rarely an issue.

One area that it does make a difference is when searching for a product or article on the internet. We conducted a quick experiment using HO and then H0 and sure enough different results were produced. Maybe this is something to bear in mind if indulging in a spot of internet shopping for your latest brand new locomotive!

But which is correct? Although different countries will have different opinions on the matter, if you trace the gauge's history back to the very beginning then the answer is H0 (zero) is the correct term to use.

The name H0 derives from a post WW1 model railway industry creating a smaller gauge than the already established 0, 1, 2 and 3 gauges, the aim was to create a smaller gauge to appeal to everyday families.

H0 gauge was created and is roughly half the size of 0 gauge, this is what H0 stands for (half of 0 gauge). The 0 in 0 gauge is clearly a number as it is in a number sequence thus the only conclusion can be that H0 too is constructed using a number.

Funnily enough, it is usually us Brits that get it wrong and often use HO. This is probably because we British are more likely to use the same verbalisation for the letter O and the number 0 pronouncing them both "ow".

Should we loose sleep over this? We'll tell you in the morning!