Assertion: hp lamp | /r/CapableOf | produce around 100 lumens per watt
Facets:
value: at introduction
type: TEMPORAL
Source sentences:
text: The first commercial high-pressure sodium lamps were available in 1965 from companies in the United States, the United Kingdom, and the Netherlands; at introduction a 400 watt lamp would produce around 100 lumens per watt.
text: The first commercial high-pressure sodium lamps were available in 1965 from companies in the United States, the United Kingdom, and the Netherlands; at introduction a 400 watt lamp would produce around 100 lumens per watt.