Under the wording of the Workplace Restrictions Order half-face shields/visors as pictured below, do not fall under the legal definition of a mask or visor and so do not comply with the law.
Based on the design they are not deemed fit for purpose in being able to prevent the release of respiratory droplets. It is also worth noting there does not appear to be any published research available on their effectiveness which is in stark contrast to the extensive research (and international guidelines) on fabric masks and full-face shields/visors.
Due to the above they are therefore not recommended and fall outside the law.
Government of Jersey