The ratings were introduced to give customers clear information about the hygiene standards of premises selling food.
Inspections are carried out by local authorities.
Businesses are given a rating from 0 to 5, with the latter being the highest that a premises can be awarded.
Here is what each one means:
5 – hygiene standards are very good
4 – hygiene standards are good
3 – hygiene standards are generally satisfactory
2 – some improvement is necessary
1 – major improvement is necessary
0 – urgent improvement is required
See the ratings of 9 businesses visited by inspectors since May in Portsmouth in our gallery below.