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

Methenamine

Methenamine is crystallizes from ethanol as colorless, hygroscopic rhombododecahedra and is odorless.

CAS 100-97-0 C6H12N4 140.19 g/mol Warning

01 · Identification

What Methenamine is

Methenamine is crystallizes from ethanol as colorless, hygroscopic rhombododecahedra and is odorless. Its molecular formula is C6H12N4 and its molecular weight is 140.19 g/mol. It melts at 129 °C.

Under the GHS it carries the signal word Warning.

02 · Identifiers

Methenamine identifiers and molecular data

Methenamine CAS number and EC number

CAS number100-97-0
EC number202-905-8
Index number (CLP Annex VI)612-101-00-2

Methenamine molecular formula and molecular weight

Molecular formulaC6H12N4
Molecular weight140.19 g/mol

Other names for Methenamine

  • hexamethylenetetramine

03 · GHS classification

Methenamine hazard classification

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

Methenamine pictograms and signal word

Signal wordWarning

Methenamine hazard class and category

GHS hazard classes Methenamine falls into
Hazard class Category From code Pictogram
Flammable solids GHS chapter 2.7 Category 1 or 2 H228 GHS02
Skin sensitisation GHS chapter 3.4 Category 1 or 1A or 1B H317 GHS07

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.

Methenamine hazard statements (H-codes)

Hazard statements assigned to Methenamine
CodeHazard statement
H228 Flammable solid.
H317 May cause an allergic skin reaction.

This page lists only the codes assigned to Methenamine. 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 Methenamine

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 Methenamine 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

Methenamine precautionary statements

CLP Annex VI assigns 5 precautionary statements to Methenamine. 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.

Response

What to do once exposure, spillage or fire has already happened.

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

Methenamine 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 метенамин хексаметилентетрамин
Spanish español Metenamina hexametilentetraamina
Czech čeština methenamin hexamethylentetraminurotropin1,3,5,7-tetraazaadamantan
Danish dansk methenamin hexamethylentetramin
German Deutsch Methenamin Hexamethylentetramin
Estonian eesti meteenamiin heksametüleentetramiin
Greek ελληνικά μεθεναμίνη εξαμεθυλενοτετραμίνη
English English methenamine hexamethylenetetramine
French français méthénamine hexaméthylènetétramine
Croatian hrvatski metenamin heksametilentetramin
Italian italiano metenammina esametilentetrammina
Latvian latviešu metēnamīns heksametilēntetramīns
Lithuanian lietuvių metenaminas heksametilentetraminas
Hungarian magyar meténamin hexametiléntetramin
Maltese Malti metenammina essametilentetrammina
Dutch Nederlands methenamine hexamethyleentetramine
Polish polski 1,3,5,7-tetraazaadamantan heksametylenotetraamina1,3,5,7-tetraazatricyklo[3.3.1.13,7]dekanurotropinaheksamina
Portuguese português metenamina hexametilenotetramina
Romanian română metenamină hexametilentetramină
Slovak slovenčina urotropín hexametyléntetramín1,3,5,7-tetraazaadamantán
Slovenian slovenščina metenamin heksametilentetramin
Finnish suomi meteeniamiini heksametyleenitetramiini
Swedish svenska metenamin hexametylentetramin

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

Methenamine GHS label elements

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

GHS02 Flame pictogramGHS07 Exclamation mark pictogram

Warning

Methenamine

  • Flammable solid.
  • May cause an allergic skin reaction.
  • Avoid breathing dust/fume/gas/mist/vapours/spray.
  • Contaminated work clothing should not be allowed out of the workplace.
  • Wear protective gloves/protective clothing/eye protection/face protection/hearing protection/
  • Get medical advice/attention.
  • If skin irritation or rash occurs:

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

Need this as an actual label? Open Methenamine in the GHS label constructor →

07 · Physical and chemical properties

Methenamine 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.

Methenamine boiling point

Property Value Conditions Source
Boiling point Sublimes (NTP, 1992) sublimes CAMEO

Methenamine melting point

Property Value Conditions Source
Melting point 128.5 °C (263.3 °F) range, midpoint shown HSDB
260 °C (500 °F) approximate HSDB
190 °C (374 °F) approximate HSDB

Methenamine density

Property Value Conditions Source
Density 1.3394 g/cm³ at 22 °C HSDB
1.35 g/cm³ at 20 °C CAMEO
1.27 g/cm³ at 25 °C HSDB

Methenamine solubility

Property Value Conditions Source
Solubility Freely soluble in water; practically insoluble in petroleum ether HSDB
In water, 302,300 mg/L at 25 °C at 25 °C HSDB

Methenamine vapor pressure

Property Value Conditions Source
Vapor pressure 0.00061 mmHg at 25 °C HSDB
0.004 mmHg Haz-Map

Methenamine flash point

Property Value Conditions Source
Flash point 250 °C (482 °F) HSDB

Methenamine autoignition temperature

Property Value Conditions Source
Autoignition temperature 390 °C (734 °F) ICSC
371.11 °C (700 °F) above this value CAMEO

Methenamine lower explosive limit (LEL)

Property Value Conditions Source
Lower explosive limit (LEL) Dust explosion possible if in powder or granular form, mixed with air. HSDB

Methenamine vapor density

Property Value Conditions Source
Vapor density 4.9 (air = 1) HSDB

Methenamine critical temperature and pressure

Property Value Conditions Source
Critical temperature and pressure 563.85 °C (1046.9 °F) HSDB

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

08 · Fire and explosion

Methenamine fire and explosion behaviour

These are descriptions rather than measured values, so they are kept out of the table above and quoted here with the source that reported them.

Methenamine fire potential

Combustible.

Source: Hazardous Substances Data Bank (HSDB)

Solubility

Solubility of methenamine in 100 g of various solvents at 20 °C is: 13.4 g chloroform, 7.25 g in methanol, 2.89 g in absolute ethanol, 0.65 g in acetone, 0.23 g in benzene, 0.14 g in xylene, 0.06 g in ether, and near zero in petroleum ether.

Source: HSDB

09 · Handling and storage

Methenamine storage and handling

Methenamine safe storage

Separated from strong acids and strong oxidants. Dry.

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

Methenamine storage conditions

Keep container tightly closed in a dry and well-ventilated place. Hygroscopic. Storage class (TRGS 510): Flammable solid hazardous materials

Source: Hazardous Substances Data Bank (HSDB)

Methenamine incompatible materials

Incompatible materials: Strong acids, acids, strong oxidizing agents

Source: Hazardous Substances Data Bank (HSDB)

Methenamine reactivity

HEXAMETHYLENETETRAMINE is hygroscopic. It is sensitive to exposure to heat. This chemical is incompatible with oxidizing agents. It is also incompatible with acids. It reacts violently with sodium peroxide. It reacts explosively with 1-bromopentaborane(9) at temperatures above 194 °F. The complex with iodine deflagrates at 280 °F. The 1:1 addition complex with iodoform has exploded at 352 °F. It is corrosive to some metals, such as aluminum and zinc (NTP, 1992). Special Hazards of Combustion Products: Formaldehyde gas and ammonia may be given off when hot (USCG, 1999).

Source: CAMEO Chemicals

Planning storage for a mix of chemicals? Check Methenamine in the storage compatibility matrix →

10 · Questions

Methenamine — frequently asked questions

What is the CAS number of Methenamine?

The CAS number of Methenamine is 100-97-0. Its EC number is 202-905-8.

What is the chemical formula of Methenamine?

The molecular formula of Methenamine is C6H12N4 and its molecular weight is 140.19 g/mol.

What does a Methenamine label have to show?

Under CLP Annex VI the label for Methenamine carries the pictograms Flame and Exclamation mark and the signal word is Warning.

Is Methenamine flammable?

Yes. CLP Annex VI assigns Methenamine H228 — flammable solid. The flash point reported for it is 250 °C (482 °F) (HSDB).

Is Methenamine a carcinogen?

CLP Annex VI records no harmonised carcinogenicity classification for Methenamine. Annex VI is a list of agreed classifications, not a list of substances found safe, so this is an absence of a classification rather than a clean bill of health.

What is the boiling point of Methenamine?

The boiling point reported for Methenamine is Sublimes (NTP, 1992), sublimes (CAMEO).

What is the melting point of Methenamine?

The melting point reported for Methenamine is 128.5 °C (263.3 °F), range, midpoint shown (HSDB).

How should Methenamine be stored?

Keep container tightly closed in a dry and well-ventilated place. Hygroscopic. Storage class (TRGS 510): Flammable solid hazardous materials (Hazardous Substances Data Bank (HSDB))

Nearby

Substances next to Methenamine

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