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Decimals Score a Point on International Standards

For Immediate Release: November 22, 2006


Contact: Michael Baum

We're in the end game. It soon may be possible to write international standards documents with decimal points in them. The issue is more than academic—it can affect sales of U.S. exports. The breakthrough comes as a result of dogged determination on the part of the National Institute of Standards and Technology (NIST) and ANSI, the official U.S. representative body in major international standards organizations.

Until recently, the rule at the International Organization for Standardization (ISO—the world's largest developer of standards) and the International Electrotechnical Commission (IEC—the leading global electrical and electronic standards organization) was that all numbers with a decimal part must be written in formal documents with a comma decimal separator, the prevailing fashion in Europe. The constant pi, for example, starts 3,141 592 653.

This had been something of an irritant for the English-speaking world (plus such notable countries as China, India and Japan) where the decimal point is used. Moreover, it could be expensive. Countries that adopted labeling or import documentation regulations based on ISO or IEC standards could block imports from the U.S. on the strength of decimal points in their specifications.

That sort of change doesn't happen overnight. The first step was to secure a resolution by the General Conference on Weights and Measures (CGPM—the reigning international treaty organization dealing with measurement) endorsing the use of the point on the line as a decimal sign. That was in 2003. Then NIST, working through ANSI, went to work to get revisions to the formal ISO and IEC documentation standards and procedures eliminating language that forbade the use of the decimal point. In June, ISO agree to make such revisions subject to IEC agreement and an effective implementation plan. In September, IEC agreed with ISO.

The last remaining hurdle is to develop the implementation plan that makes sure that ISO and IEC staff change their publication style policies to reflect the now-legitimate use of decimal points in English-language documents. We'll make a point of it.