The phrase "rigorous restrictions" is grammatically correct and can be used in written English.
It means strict limitations or rules that are strictly enforced. Example: The city has implemented rigorous restrictions on water usage in order to conserve resources during the drought.
Historical preservation laws known as denkmalschutz place even more rigorous restrictions on almost any change.
Developers of modern diesel engines have to face rigorous restrictions in emission of nitrogen-oxides and particulate matter.
Specifically, it should call on its European allies to impose more rigorous restrictions on exports to Libya that could be used to produce chemical weapons.
There could, however, be some kind of trade-off whereby the West would tolerate a civilian nuclear programme (which is all Iran has, it says) in return for more rigorous restrictions on it.
These restaurants are heavily taxed by the state and subject to rigorous restrictions as to size and menu, restrictions that are generally observed in the breach, and they continue to flourish.
Rigorous restrictions on reporting the news have been put in place as the army attempts to fight off a critical campaign for the Jaffna Peninsula by the Tamil Tiger rebels.
When rigorous restriction on all transport modes is combined with AH, the delays (peak appearing after the 10th month) are possible to allow vaccine production (i.e. beyond the nine months following the first global import to Hong Kong, during which time a vaccine program was developed and administered to the local public).
More importantly, enforcing rigorous travel restrictions has been undoubtedly unrealistic to date, since such restrictions would substantially degrade the local economy.
Hollingsworth et al. [ 6] concluded that containment of a pandemic influenza strain requires rigorous travel restrictions and small numbers of local infectious inhabitants.
Safety concerns on rigorous sodium restriction should not distract from the considerable potential benefits of moderate sodium restriction in the vast majority of CKD patients, in whom sodium intake is high or very high.
This use of equitable powers is a contribution of the courts in furthering the harmonious relation between state and federal authority without the need of rigorous congressional restriction of those powers". 312 U. S., at 500-501 (citatiomittedtted).
