go-clp

go-clp is a zero-dependency Go library for deterministic EU CLP/GHS mixture classification. It calculates mixture hazards, constructs labels, generates UFIs, applies date-aware Annex VI data, and produces Greek and English presentation text.

The classification core performs no I/O and has no mutable external state. Runtime use requires only the Go standard library.

go get github.com/cpouldev/go-clp

Go 1.23 or newer is required.

Classify concentration-resolved components with ClassifyMixture:

package main

import (
    "fmt"

    clp "github.com/cpouldev/go-clp"
)

func main() {
    result := clp.ClassifyMixture([]clp.ClassComponent{
        {
            Name:                "sensitising fragrance",
            ConcentrationPct:    1.2,
            ConcentrationLowPct: 1.2,
            SkinSensCategory:    "1B",
            Hazards: []clp.ComponentHazard{
                {
                    Class:    "Skin sensitisation",
                    Category: "1B",
                    HCodes:   []string{"H317"},
                },
            },
        },
    }, nil, false)

    fmt.Println(result.Label.SignalWord) // Warning
    fmt.Println(result.Label.HCodes)     // [H317]
    fmt.Println(result.Label.Pictograms) // [GHS07]
}

Use ParseHazardClass at input boundaries to reject unknown class names before classification.

RunEngine accepts recipe quantities and structured supplier SDS extractions. It computes concentrations, applies regulatory registries, classifies the mixture, evaluates supported transport rules, generates a UFI when required, and builds both language views.

date := time.Date(2026, 8, 2, 0, 0, 0, 0, time.UTC)
harmonised, err := annexvi.AsOf(date)
if err != nil {
    log.Fatal(err)
}

fragranceAllergens, err := allergens.Load()
if err != nil {
    log.Fatal(err)
}

result := clp.RunEngine(clp.EngineInput{
    Recipe:         &clp.Recipe{Name: "Example fragrance", FormulationNumber: 123456},
    CompanyCountry: "FR",
    CompanyVAT:     "AB123456789",
    ProductClass:   clp.ClassLiquid,
    Lines: []clp.RecipeLine{
        {MaterialID: "fragrance", MaterialName: "Fragrance concentrate", Quantity: 1.2, Unit: "g"},
        {MaterialID: "carrier", MaterialName: "Carrier", Quantity: 98.8, Unit: "g"},
    },
    Extractions: map[string]clp.ParsedExtraction{
        "fragrance": {
            Substances: []clp.ParsedSubstance{
                {
                    Name:               "Limonene",
                    CasNumber:          "5989-27-5",
                    ConcentrationRange: "100%",
                    HCodes:             []string{"H317"},
                    Hazards: []clp.ParsedHazard{
                        {Class: "Skin sensitisation", Category: "1B"},
                    },
                },
            },
        },
    },
    Harmonised: harmonised,
    AllergenCAS: fragranceAllergens.CAS,
    InciNames:   fragranceAllergens.INCIByCAS,
})

for _, flag := range result.Flags {
    log.Printf("%s: %s", flag.Severity, flag.Message)
}

Treat every SeverityBlock flag as unresolved input. SeverityWarn and SeverityInfo identify decisions that need review or confirmation.

code, err := ufi.Generate("FR", "AB123456789", 123456)
if err != nil {
    log.Fatal(err)
}
fmt.Println(code) // 27W0-KC81-E00T-V314
fmt.Println(ufi.Validate(code)) // true

ufi.Generate supports the country-specific VAT schemes published by ECHA and EU company keys. Formulation numbers must be in 0..268435455. Validation checks syntax and checksum; it does not submit a Poison Centre Notification.

registry, err := annexvi.AsOf(time.Date(2027, 2, 1, 0, 0, 0, 0, time.UTC))
input.Harmonised = registry

The embedded dataset contains the 4,419-entry ATP22 state and 32 ATP23 insertions or replacements. ATP23 applies from 1 February 2027. Dates before 1 May 2026 return an empty registry; the package does not infer voluntary early application.

The allergens package embeds 81 Annex III references, 167 distinct CAS numbers, and 140 distinct Common Ingredients Glossary names. It feeds the engine's advisory allergen coverage check and never changes CLP classification.

registry, err := allergens.Load()
if err != nil {
    log.Fatal(err)
}
required, err := allergens.RequiresDisclosure(allergens.LeaveOn, 0.0011)
if err != nil {
    log.Fatal(err)
}
fmt.Println(required) // true

input.AllergenCAS = registry.CAS
input.InciNames = registry.INCIByCAS

The individual-labelling thresholds are concentrations above 0.001% for leave-on products and 0.01% for rinse-off products. Callers remain responsible for transition rules and the complete Cosmetics Regulation assessment.

view := clp.BuildPresentation(clp.SdsClassification{
    Label: clp.SdsLabel{SignalWord: "Warning", HCodes: []string{"H317"}},
})

fmt.Println(view.EN.HStatements[0].Text)
fmt.Println(view.EL.HStatements[0].Text)

Runnable examples also live in example_test.go and each public subpackage.

.
├── api.go                 Public root-package facade
├── allergens/             Cosmetics Annex III registry
├── annexvi/               Harmonised classification registry
├── ufi/                   UFI generation and validation
├── internal/core/         Classification engine and white-box tests
├── internal/*source/      EUR-Lex build-time parsers
├── cmd/                   Data generators and private comparison tool
└── .github/workflows/     Public CI, release automation, private ECHA comparison

go test ./...          # all tests and examples
go test -race ./...    # race detector
go vet ./...           # static analysis
gofmt -l .             # formatting check; should print nothing
go build ./...         # compile every package and command

Regenerate the pinned EUR-Lex datasets with go generate ./annexvi and go generate ./allergens. To compare a manually exported ECHA CSV privately, run:

go run ./cmd/annexvi-crosscheck -echa /secure/path/annex-vi.csv

The command performs no network request and writes no ECHA-derived artifact.

Release Please manages releases from Conventional Commits on main. Merge the generated release pull request to create the GitHub release and its vMAJOR.MINOR.PATCH tag; never edit versions or create release tags by hand. The workflow needs a repository Actions secret, RELEASE_PLEASE_TOKEN, that can write contents, issues, and pull requests. Release Please also generates CHANGELOG.md, tracks the version in .release-please-manifest.json, and reads its settings from release-please-config.json.

• The engine does not implement Annex I §1.1.3 bridging principles.
• Physical hazards cover flash-point-gated flammable liquids only.
• Transport covers a fragrance-focused subset: UN 1170, 1197, 1266, 3077, and 3082, including LQ/EQ and SP375 decisions.
• Rendered regulatory text is available in Greek and English only.
• Consolidated EUR-Lex texts aid documentation but have no legal force.

Code is licensed under Apache-2.0. Embedded EU reference data is reused under CC BY 4.0. See NOTICE for sources, transformations, and attribution.