How to identify lead paint<br>Determine if the paint is from 1970 or earlier. Most homes built before 1970 often have lead-based paint on the walls, doorways, stairwells, and baseboards. If your home is old and you know it was built in the early or mid 1900s, it may have lead-based paint.
All homes built before 1970 have lead-based paint
This statement is definitely incorrect based on the context, because the context says "most" homes, not "all." The system may have thought this statement belonged in neither category, because we do no know, from the context, what percentage of homes have lead in them.
( z1 have :ARG0 ( z2 home :mod ( z3 all ) :ARG1-of ( z4 build :time ( z5 before :op ( z6 date-entity :year 1970 ) ) ) ) :ARG1 ( z7 paint :ARG1-of ( z8 base :ARG2 ( z9 lead ) ) ) )