About: http://webisa.webdatacommons.org/181821308

Property	Value
http://www.w3.org/1999/02/22-rdf-syntax-ns#type	http://www.w3.org/ns/prov#Entity
http://www.w3.org/ns/prov#value	A switch, bar, sensor, or other mechanism that interrupts the machine's operating cycle to prevent workers or any parts of their bodies from entering dangerous areas during machine cycles.
http://www.w3.org/ns/prov#wasQuotedFrom	toolingu.com