The Swedish TCO organization provides voluntary certifications for various products, which includes monitors. It is important to understand that TCO certifications are "living documents", i.e. new requirements is added over time that is reflected by new TCO names. They started originally with "MPR" requirements in 1980 where CRT monitors exist due to radiation issues especially for pregnant women in offices.
In 1992 they offered TCO92 followed by TCO96, TCO99, TCO-03 and now TCO certified 5.0 und TCO certified 6.0.
Each new version includes new requirements. Only where studies showed no relevance of previously added requirements, TCO may remove requirements or change limit values.
Monitor manufacturers usually certify a new monitor (before product launch) with the valid TCO certification. And TCO cancel older certification after a grace period. That means one cannot certify TCO-03 nowadays because it is no longer offered by TCO at all. See details at http://tcodevelopment.com/manufacturer-resources/product-categories-2/displays/
HP business monitors have a valid TCO certification by the time the product is introduced to the market.