# Measures

## What measures are

Measures are the building blocks of any trade tariff. They link everything together. Any law that has an effect on the trade of goods becomes one or more measures.
 
A measure is what makes border systems react when a trader imports or exports goods from one country to another. If there is no measure, then the border systems will not react.
 
A measure is a single line on [the UK Tariff](https://www.trade-tariff.service.gov.uk/find_commodity). Some commodity codes have hundreds of measures assigned to them.
 
For example, if you [search the Tariff for cherry tomatoes](https://www.trade-tariff.service.gov.uk/commodities/0702000007#import), you will find many 'measure types' listed against this commodity code. Each one of these is a measure. 

A measure is not an overarching policy or specific enactment of that policy. In tariff terms, that is a regulation.

```dot
graph "Measures and Regulations" {
  rankdir=LR
  node [shape=box]

  measure1 [label=Measure]
  measure2 [label=Measure]
  measure3 [label=Measure]
  measure4 [label=Measure]
  
  "Regulation" -- measure1
  "Regulation" -- measure2
  "Regulation" -- measure3
  "Regulation" -- measure4
}
```

## How a measure is structured

A measure consists of a series of parts. 
 
### Goods classification
 
A measure applies to a single commodity code in the full list of products in the Tariff. This list is called [the goods classification](https://uktrade.github.io/tariff-data-manual/documentation/data-structures/commodity-codes.html#commodity-codes).

While a trade instrument (FTA, import restriction etc.) may and is likely to cover multiple commodity codes, this results in the creation of many individual measures.

The Tariff database employs inheritance to apply measures – there are up to 13 tiers in the commodity code hierarchy. In theory, a measure can be applied at any tier in that hierarchy and inherited down. In practice, measures are very rarely assigned at HS chapter (the first tier in the hierarchy). While this inheritance is great for accelerating the creation of measures, it brings complexity in terms of business rule adherence. A measure cannot exist in a hierarchy in the same context (i.e. same measure type, same comm code tree, same date period, same measure type etc.) more than once. So there is no concept of applying a measure at a higher tier in the database and then having it superseded by a more granular exception in a lower tier – you need to be explicit when assigning measures. Thus, if  commodity X has 10 children, 9 of which require a 0% duty and 1 of which requires a 50% duty, then you must assign the duties explicitly to all 10 commodities.

A commodity code or goods nomenclature item is assigned to a measure via two fields, both of which point to the same data item (goods_nomenclature_item_id and goods_nomenclature_sid). While a commodity code is fully characterised also by its productline_suffix, all measures must be assigned to commodity codes with a productline_suffix of 80, therefore this data would be superfluous on the the measure table.

 
### Geographical area
 
A measure applies to one geographical area. A geographical area can be a single country or a group of countries. Within country groups individual countries may be excluded from measures. Read more about [geographical areas](https://uktrade.github.io/tariff-data-manual/documentation/data-structures/geographical-areas.html#geographical-areas).
 
### Base regulation
 
A measure must have a single regulation which provides its justification in law. Read more about [regulations](https://uktrade.github.io/tariff-data-manual/documentation/data-structures/regulations.html#measure-generating-regulations).
 
### Additional code
 
Additional codes are primarily used to identify companies which trade remedies should be assigned to. Read more about [additional codes](https://uktrade.github.io/tariff-data-manual/documentation/data-structures/additional-codes.html#additional-code-types-data-entities). 
 
### Measure component
 
Measure component is the term used to describe the elements that make up a tariff duty. Read more about [measure components](https://uktrade.github.io/tariff-data-manual/documentation/data-structures/measure-components.html#measure-components). 
 
### Quota
 
Quotas allow for goods to be imported at a reduced or zero duty rate until the quota runs out. Quotas are separate objects in the database, it is not possible to allow traders to declare against quotas unless there is a quota measure exposing its presence to the trader. Read more about [quotas](https://uktrade.github.io/tariff-data-manual/documentation/data-structures/quotas.html#quotas).
 
### Measure type
 
Each measure belongs to a specific measure type. These describe to the border systems how to execute some kind of action on the trade in question. There are about 85 different measure types. About 8 of these are related to trade remedies. Read more about [measure types](https://uktrade.github.io/tariff-data-manual/documentation/data-structures/measure-types.html#measure-types).
 
### Footnote
 
Footnotes help explain the measure. It is possible to apply footnotes to both commodity codes and to measures. As with anything else associated to the measure, the footnote is inherited down to child commodity codes – therefore if a measure with a footnote is assigned at HS chapter, then both the measure and the footnote are inherited down to all commodity codes in that chapter. A footnote is connected to the measure by a linking table. Footnotes are linked to measures for the entirety of the measure’s duration – the association does not have its own start and end dates – which differs from footnotes’ association with commodity codes, which are dated. Read more about [footnotes](https://uktrade.github.io/tariff-data-manual/documentation/data-structures/footnotes.html#footnotes). 
 
### Measure condition
 
A measure can have any number of conditions that define the rules under certain circumstances. They are used to desctibe to border systems duties or restrictions that may apply under certain circumstances. Read more about [measure conditions](https://uktrade.github.io/tariff-data-manual/documentation/data-structures/measure-conditions.html#measure-conditions).
 
### Certificate
 
Certificates link to the licences or other documents that are needed to bring goods through customs. Read more about [certificates](https://uktrade.github.io/tariff-data-manual/documentation/data-structures/certificates.html#certificates). 

### Validity dates
Measures are valid from their validity start date to their end date, unless they're suspended. Validity start dates are mandatory, whereas validity end dates are optional and usually left blank. Measure start dates usually coincide with the start dates of the regulations that engender them, though that is not always the case: the regulation also usually has no end date. Read more about [validity dates](https://uktrade.github.io/tariff-data-manual/documentation/data-structures/validity-dates.html#validity-dates).


## National prohibition and restriction types

There are about 14 national prohibition and restriction type measures. There is no differentiation between measures formerly provided by the EU and national prohibition and restriction types.

| ID | Description |  UK measure type |
|-|-|-|
| AHC | Animal Health Certificate |  350 |
| AIL | Health and Safety Executive Import Licensing Firearms and Ammunition |  351 |
| ATT | Attestation Document (horticulture and potatoes) |  352 |
| CEX | DCMS Open General Export Licence |  353 |
| COE | Home Office Controlled Drugs (export) |  354 |
| COI | HMI Conformity Certificate (fruit and veg) issued in UK |  355 |
| CVD | Common Veterinary Entry Document (CVED) |  356 |
| EQC | Certificate of Conformity |  357 |
| HOP | Home Office pre-cursor chemical authorisation | 358 |
| HSE | Health and Safety Executive (imports) |  359 |
| PHC | Phytosanitary Certificate (import) |  360 |
| PRE | Home Office Pre-cursor chemicals |  361 |
| PRT | Home Office Controlled Drugs (import) |  362 |
| QRC | Quarantine Release Certificate |  363 |

The Common Veterinary Entry Document (CVD) measure type is exactly the same as measure type 410 (Veterinary control).


## Validation rules

| Code | Description |
|---|---|
| MA1 | [Uniqueness](Validity-rules;-Uniqueness.md) rule for codes of measure actions. |
| MA4 | [Validity contained](Validity-rules;-Validity-contained.md) rule for measure actions used in measures. |
| ME1 | [Uniqueness](Validity-rules;-Uniqueness.md) rule for the combination of measure type, geographical area, goods nomenclature item id, additional code type, additional code, order number, reduction indicator and start date. |
| ME10 | The order number must be specified if the “order number flag” (specified in the measure type record) has the value “mandatory”. If the flag is set to “not permitted” then the field cannot be entered. |
| ME104 | The justification regulation must be either: the measure’s measure-generating regulation, or a measure-generating regulation, valid on the day after the measure’s (explicit) end date. If the measure’s measure-generating regulation is ‘approved’, then so must be the justification regulation. |
| ME115 | [Validity contained](Validity-rules;-Validity-contained.md) rule for additional codes referenced in measures. |
| ME116 | [Validity contained](Validity-rules;-Validity-contained.md) rule for quota order numbers used in measures. |
| ME117 | When a measure has a quota measure type then the origin must exist as a quota order number origin. Only origins for quota order numbers managed by the first come first served principle are in scope; these order number are starting with ‘09’; except order numbers starting with ‘094’. |
| ME119 | [Validity contained](Validity-rules;-Validity-contained.md) rule for quota order number origins used in measures. |
| ME12 | If the additional code is specified then the additional code type must have a relationship with the measure type. |
| ME16 | Integrating a measure with an additional code when an equivalent or overlapping measures without additional code already exists and vice-versa, should be forbidden. |
| ME17 | If the additional code type has as application “non-Meursing” then the additional code must exist as a non-Meursing additional code. UK tariff does not use meursing tables, so this is essentially saying that an additional code must exist. |
| ME2 | The measure type must exist. |
| ME24 | The role + regulation id must exist. If no measure start date is specified it defaults to the regulation start date. |
| ME25 | If the measure’s end date is specified (implicitly or explicitly) then the start date of the measure must be less than or equal to the end date. |
| ME27 | The entered regulation may not be fully replaced. |
| ME3 | [Validity contained](Validity-rules;-Validity-contained.md) rule for measure types used in measures. |
| ME32 | There may be no overlap in time with other measure occurrences with a goods code in the same nomenclature hierarchy which references the same measure type, geo area, order number, additional code and reduction indicator. This rule is not applicable for Meursing additional codes. |
| ME33 | A justification regulation may not be entered if the measure end date is not filled in. |
| ME34 | A justification regulation must be entered if the measure end date is filled in. |
| ME4 | [Mandatory subrecord](Validation-rules;-Mandatory-subrecord.md) rule for geographical areas referenced by measures. |
| ME40 | If the flag “duty expression” on measure type is “mandatory” then at least one measure component or measure condition component record must be specified. If the flag is set “not permitted” then no measure component or measure condition component must exist. Measure components and measure condition components are mutually exclusive. A measure can have either components or condition components (if the “duty expression” flag is “mandatory” or “optional”) but not both. This describes the fact that measures of certain types MUST have components (duties) assigned to them, whereas others must not. Note the sub-clause also – if the value of the field “Component applicable” is set to 1 (mandatory) on a measure type, then when the measure is created, there must be either measure components or measure condition components assigned to the measure, but not both. CDS will generate errors if either of these conditions are not met. |
| ME5 | [Validity contained](Validity-rules;-Validity-contained.md) rule for geographical areas referenced by measures. |
| ME53 | [Mandatory subrecord](Validation-rules;-Mandatory-subrecord.md) rule for referenced measure conditions. |
| ME6 | [Mandatory subrecord](Validation-rules;-Mandatory-subrecord.md) rule for the referenced goods code. |
| ME65 | An exclusion can only be entered if the measure is applicable to a geographical area group (area code = 1). |
| ME66 | The excluded geographical area must be a member of the geographical area group. |
| ME67 | [Validity contained](Validity-rules;-Validity-contained.md) rule for the membership period of the excluded geographical area. |
| ME68 | The same geographical area can only be excluded once by the same measure. |
| ME69 | [Mandatory subrecord](Validation-rules;-Mandatory-subrecord.md) rule for associated footnotes. |
| ME7 | The goods nomenclature code must be a product code. It may not be an intermediate line. |
| ME70 | The same footnote can only be associated once with the same measure. |
| ME71 | Footnotes with a footnote type for which the application type = “CN footnotes” cannot be associated with TARIC codes (codes with pos 9-10 different from 00). |
| ME73 | [Validity contained](Validity-rules;-Validity-contained.md) rule for referenced footnotes. |
| ME8 | [Validity contained](Validity-rules;-Validity-contained.md) rule for referenced goods codes. |
| ME87 | The validity period of the measure (implicit or explicit) must reside within the effective validity period of its supporting regulation. The effective validity period is the validity period of the regulation taking into account extensions and abrogation. |
| ME88 | The level of the goods code cannot exceed the explosion level of the measure type. |
| ME9 | If no additional code is specified then the goods code is mandatory. |
| QuotaOriginMatchingArea | When a quota order number is used in a measure then the quota order number origin’s geographical area(s) must match those of the measure. |

Read more in the [system documentation](https://uktrade.github.io/tamato/html/business_rules/measures.html).