Provenance

Reference data from EU CLP Annex VI and published regulations — verify against your supplier's SDS before use.

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Substance profile

O-Phenylenediamine

O-Phenylenediamine is brownish-yellow leaflets from water; plates from chloroform.

CAS 95-54-5 C6H8N2 108.14 g/mol Danger

01 · Identification

What O-Phenylenediamine is

O-Phenylenediamine is brownish-yellow leaflets from water; plates from chloroform. Its molecular formula is C6H8N2 and its molecular weight is 108.14 g/mol. It boils at 257 °C, melts at 102 °C.

Under the GHS it carries the signal word Danger.

02 · Identifiers

O-Phenylenediamine identifiers and molecular data

O-Phenylenediamine CAS number and EC number

CAS number95-54-5
EC number202-430-6
Index number (CLP Annex VI)612-145-00-2

O-Phenylenediamine molecular formula and molecular weight

Molecular formulaC6H8N2
Molecular weight108.14 g/mol

03 · GHS classification

O-Phenylenediamine hazard classification

Harmonised classification under CLP Annex VI. This is the legally binding classification in the EU; other jurisdictions may differ.

O-Phenylenediamine pictograms and signal word

Signal wordDanger

O-Phenylenediamine hazard class and category

GHS hazard classes O-Phenylenediamine falls into
Hazard class Category From code Pictogram
Acute toxicity - oral GHS chapter 3.1 Category 3 H301 GHS06
Acute toxicity - dermal GHS chapter 3.1 Category 4 H312 GHS07
Acute toxicity - inhalation GHS chapter 3.1 Category 4 H332 GHS07
Serious eye damage/eye irritation GHS chapter 3.3 Category 2A H319 GHS07
Skin sensitisation GHS chapter 3.4 Category 1 or 1A or 1B H317 GHS07
Germ cell mutagenicity GHS chapter 3.5 Category 2 H341 GHS08
Carcinogenicity GHS chapter 3.6 Category 2 H351 GHS08
Hazardous to the aquatic environment - acute GHS chapter 4.1 Category 1 H400 GHS09
Hazardous to the aquatic environment - chronic GHS chapter 4.1 Category 1 H410 GHS09

Where two values are shown with “or”, the hazard statement is shared by more than one category or by more than one class, and the code alone does not say which. H272, for example, belongs to oxidising liquids and to oxidising solids — the physical state decides. The binding answer for a specific entry is in the CLP Annex VI table itself.

O-Phenylenediamine hazard statements (H-codes)

Hazard statements assigned to O-Phenylenediamine
CodeHazard statement
H351 Suspected of causing cancer <state route of exposure if it is conclusively proven that no other routes of exposure cause the hazard>.
H341 Suspected of causing genetic defects <state route of exposure if it is conclusively proven that no other routes of exposure cause the hazard>.
H301 Toxic if swallowed.
H332 Harmful if inhaled.
H312 Harmful in contact with skin.
H319 Causes serious eye irritation.
H317 May cause an allergic skin reaction.
H400 Very toxic to aquatic life.
H410 Very toxic to aquatic life with long lasting effects.

This page lists only the codes assigned to O-Phenylenediamine. The full reference lives on the hazard statements hub, the precautionary statements hub and the GHS pictograms hub.

Safety Data Sheet

Getting an SDS for O-Phenylenediamine

A Safety Data Sheet is written for a product, not for a substance: the supplier of the grade you actually buy issues it, so two suppliers of O-Phenylenediamine issue two different sheets. That is why there is no single authoritative SDS for a substance to download — what there is, is the job of collecting the sheets for the products you hold and keeping them current as suppliers revise them.

04 · Precautionary statements

O-Phenylenediamine precautionary statements

CLP Annex VI assigns 24 precautionary statements to O-Phenylenediamine. They are grouped the way a label groups them: what to do before handling, what to do when something has already happened, how to store it and how to dispose of it.

Disposal

What has to happen to the contents and the empty container.

Reading the notation. is a blank the supplier fills in — not a truncated sentence.· [square brackets] mark a part printed only when it applies.

05 · Names in the regulation

O-Phenylenediamine name in 23 EU languages

CLP Annex VI Part 3 is published in every language edition of the regulation, and the identification column is written out in each of them. Nothing below is translated by us: each line is the name as that edition prints it. Under Art. 18(2) the substance name from Annex VI is a lawful product identifier, so this is the wording to put on a label going to that market — and where the cell lists several designations, any one of them qualifies.

Language Name in CLP Annex VI Part 3
Bulgarian български o -фенилендиамин
Spanish español o -Fenilendiamina
Czech čeština o -fenylendiamin
Danish dansk o -phenylendiamin
German Deutsch o-Phenylendiamin 1,2-Diaminobenzol
Estonian eesti o -fenüleendiamiin
Greek ελληνικά o -φαινυλενοδιαμίνη
English English o -phenylenediamine
French français o -phénylènediamine
Croatian hrvatski o -fenilendiamin
Italian italiano o -fenilendiamina
Latvian latviešu o -fenilēndiamīns
Lithuanian lietuvių o -fenilendiaminas
Hungarian magyar o -feniléndiamin
Maltese Malti o -fenilendiammina
Dutch Nederlands o -fenyleendiamine
Polish polski o -fenylenodiamina 1,2-fenylenodiamina
Portuguese português o -fenilenodiamina
Romanian română o -fenilendiamină
Slovak slovenčina orto -fenyléndiamín benzén-1,2-diamín
Slovenian slovenščina o -fenilendiamin
Finnish suomi o -fenyleenidiamiini
Swedish svenska o -fenylendiamin

All 23 language editions of Annex VI carry this entry. Irish is the twenty-fourth official EU language and has no line here for a different reason: no consolidated CLP text has ever been published in Irish, so there is no Irish edition of Annex VI to quote a name from. Source: consolidated CLP, CELEX 02008R1272, language editions. © European Union, https://eur-lex.europa.eu — only the electronic Official Journal of the European Union is authentic.

06 · Label elements

O-Phenylenediamine GHS label elements

Everything CLP Annex VI fixes for O-Phenylenediamine, laid out the way it appears on a label. The greyed lines are the parts only the supplier can fill in.

GHS06 Skull and crossbones pictogramGHS08 Health hazard pictogramGHS09 Environment pictogram

Danger

O-Phenylenediamine

  • Suspected of causing cancer <state route of exposure if it is conclusively proven that no other routes of exposure cause the hazard>.
  • Suspected of causing genetic defects <state route of exposure if it is conclusively proven that no other routes of exposure cause the hazard>.
  • Toxic if swallowed.
  • Harmful if inhaled.
  • Harmful in contact with skin.
  • Causes serious eye irritation.
  • May cause an allergic skin reaction.
  • Very toxic to aquatic life.
  • Very toxic to aquatic life with long lasting effects.
  • Obtain special instructions before use.
  • Do not breathe dust/fume/gas/mist/vapours/spray.
  • Avoid breathing dust/fume/gas/mist/vapours/spray.
  • Wash thoroughly after handling.
  • Do not eat, drink or smoke when using this product.
  • Use only outdoors or in a well-ventilated area.
  • Contaminated work clothing should not be allowed out of the workplace.
  • Avoid release to the environment.
  • Wear protective gloves/protective clothing/eye protection/face protection/hearing protection/
  • IF SWALLOWED:
  • IF ON SKIN:
  • IF INHALED:
  • IF IN EYES:
  • IF exposed or concerned:
  • Immediately call a POISON CENTER/doctor/
  • Call a POISON CENTER/doctor/ if you feel unwell.
  • Get medical advice/attention.
  • Rinse mouth.
  • If skin irritation or rash occurs:
  • If eye irritation persists:
  • Remove contact lenses, if present and easy to do. Continue rinsing.
  • Wash with plenty of water/
  • Collect spillage.
  • Dispose of contents/container to

Supplier name, address and telephone number· Product identifier·Nominal quantity

Need this as an actual label? Open O-Phenylenediamine in the GHS label constructor →

07 · Health hazards

O-Phenylenediamine health hazards and exposure limits

O-Phenylenediamine hazard summary

At lethal concentrations, exposed animals have seizures and paralysis without anesthesia. [ChemIDplus] Methemoglobinemia is observed in acute animal studies. In subchronic studies, rats have anemia and elevated liver enzymes. Critical Effects are irritation; liver; blood; [ACGIH]

Source: Haz-Map, Information on Hazardous Chemicals and Occupational Diseases

O-Phenylenediamine carcinogenicity classification

IARC classification Group 2B — Possibly carcinogenic to humans
IARC monographs Volume 123: (2020) Some Nitrobenzenes and Other Industrial Chemicals

An IARC group and a CLP classification answer different questions. IARC judges whether the evidence for cancer in humans is strong enough; CLP Annex VI is the legally binding EU classification. A substance can carry one and not the other.

08 · Physical and chemical properties

O-Phenylenediamine properties

Every value is shown with the conditions it was measured under and the source it came from. Where sources disagree, all values are listed rather than one being picked — the difference is usually a different form of the substance, not an error.

O-Phenylenediamine boiling point

Property Value Conditions Source
Boiling point 257 °C (494.6 °F) HSDB
257 °C (494.6 °F) at 760 mmHg DOE PAC
256.94 °C (494.5 °F) range, midpoint shown, at 760 mmHg CAMEO

O-Phenylenediamine melting point

Property Value Conditions Source
Melting point 102.1 °C (215.8 °F) HSDB
104 °C (219.2 °F) DOE PAC
103.06 °C (217.5 °F) range, midpoint shown CAMEO

O-Phenylenediamine solubility

Property Value Conditions Source
Solubility Because of ... limited solubility in cold water/o-phenylenediamine/ can be recrystalized from water HSDB
Freely soluble in alcohol, chloroform, ether HSDB
Soluble in water, ethyl ether, benzene, chloroform; very soluble in ethanol HSDB

O-Phenylenediamine vapor pressure

Property Value Conditions Source
Vapor pressure 0.0098 mmHg at 20 °C ICSC
0.0021 mmHg at 25 °C HSDB

O-Phenylenediamine flash point

Property Value Conditions Source
Flash point 156 °C (312.8 °F) Closed cup HSDB
156.11 °C (313 °F) CAMEO
156 °C (312.8 °F) ICSC

O-Phenylenediamine lower explosive limit (LEL)

Property Value Conditions Source
Lower explosive limit (LEL) 1.5 % by volume HSDB
Finely dispersed particles form explosive mixtures in air. HSDB

O-Phenylenediamine vapor density

Property Value Conditions Source
Vapor density 3.73 (air = 1) ICSC

Values compiled from PubChem Laboratory Chemical Safety Summary. Temperatures converted to Fahrenheit for reference.

09 · Handling and storage

O-Phenylenediamine storage and handling

O-Phenylenediamine safe storage

Separated from food and feedstuffs. Well closed.

Source: ILO-WHO International Chemical Safety Cards (ICSCs)

O-Phenylenediamine storage conditions

Separated from food and feedstuffs. Well closed.

Source: Hazardous Substances Data Bank (HSDB)

O-Phenylenediamine reactivity

1,2-PHENYLENEDIAMINE a weak aromatic amine base neutralizes acids in exothermic reactions to form salts. May be incompatible with isocyanates, halogenated organics, peroxides, phenols (acidic), epoxides, anhydrides, and acid halides. Darkens on exposure to air (Roger Patrick, DuPont Engineer).

Source: CAMEO Chemicals

Planning storage for a mix of chemicals? Check O-Phenylenediamine in the storage compatibility matrix →

10 · Questions

O-Phenylenediamine — frequently asked questions

What is the CAS number of O-Phenylenediamine?

The CAS number of O-Phenylenediamine is 95-54-5. Its EC number is 202-430-6.

What is the chemical formula of O-Phenylenediamine?

The molecular formula of O-Phenylenediamine is C6H8N2 and its molecular weight is 108.14 g/mol.

What does a O-Phenylenediamine label have to show?

Under CLP Annex VI the label for O-Phenylenediamine carries the pictograms Skull and crossbones, Health hazard and Environment and the signal word is Danger.

Is O-Phenylenediamine flammable?

CLP Annex VI assigns O-Phenylenediamine no flammability hazard class. That is not a statement that it cannot burn: the harmonised list only records the hazards that were assessed for it. The flash point reported for it is 156 °C (312.8 °F), Closed cup (HSDB).

Is O-Phenylenediamine a carcinogen?

CLP Annex VI assigns O-Phenylenediamine H351 — suspected of causing cancer. That is category 2: the evidence points that way but is not conclusive. IARC places it in Group 2B: possibly carcinogenic to humans.

What is the boiling point of O-Phenylenediamine?

The boiling point reported for O-Phenylenediamine is 257 °C (494.6 °F) (HSDB).

What is the melting point of O-Phenylenediamine?

The melting point reported for O-Phenylenediamine is 102.1 °C (215.8 °F) (HSDB).

How should O-Phenylenediamine be stored?

Separated from food and feedstuffs. Well closed. (Hazardous Substances Data Bank (HSDB))

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