How to find diffrent unit standerds relating to boilermaking

The basic principle is that it would use the customary or legal standard units for the particular country.

For instance in the US, although the metric system is legal, the American imperial (modified British) system is still used. Hence boilermaking specs and drawings would usually be in inches, feet, US ounces and pounds etc.

In Australia it has all gone metric long since, and units are in metres, mm, grams and kilograms etc. Boilermaking as a trade is nearly dead, but would be metric.

In the UK all packaging and food sales must be in metric units, but otherwise metrication is self-regulating and more or less voluntary. Because of the vast amount of equipment and tooling which has still imperial units inherent in it, much manufacturing there still uses imperial units. Boilermakers could see either system.
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