[lemma=be] [lemma=□] □ □
[lemma=be] [lemma=require] □ □
[lemma=be] [lemma=to] □ □
If the worker has received a severe acute exposure , hospitalization may be required to assure proper medical intervention . Because of the critical conditions , such as the deep and ultradeep waters and low fracture gradients , great precision is required to assure gravel-packing success . The employer is required to assure that no employee is exposed to lead at concentrations in excess of the PEL of fifty micrograms of lead per cubic meter of air ( 50 ug / m ( 3 ) ) . And this strong federal govt is required to assure all US citizens basic rights and what-not , regardless of state of residence . A full and explicit enumeration of benefits of inclusion and exclusion is required to assure that maximum benefits are achieved at minimum cost .