Chloromethanes Compared: Methyl Chloride, DCM, Chloroform and Perchloroethylene — Properties, Class and Packaging

Wed, 14 Oct 2026 · HARMONY TECHNOLOGY (ZHEJIANG) CO., LTD.

The short answer: four chlorinated products, and the one number that separates them is the boiling point — methyl chloride −24.4 °C, dichloromethane 39.6 °C, chloroform 61.12 °C, perchloroethylene 121 °C. One of the four is a liquefied gas; the other three are liquids handled at ambient pressure. That single fact decides the packaging, the transport class and the document set.

1. The four products, side by side

2. The boiling point is the purchasing decision

Read the fourth row downwards: −24.4 °C → 39.6 °C → 61.12 °C → 121 °C. A 145 °C spread across four products that a customer may buy in one enquiry.

• Methyl chloride boils below any ambient temperature, so it is never a liquid you pour — it is a liquefied gas held at its own vapour pressure, and containment must be pressure-rated. It shares that rule with the refrigerant grades in our scope, not with the three solvents.
• The two middle products are the packaging question. Dichloromethane at 39.6 °C is the one whose vapour pressure inside a drum at container temperature is a design condition; chloroform at 61.12 °C sits below it, so the same drum carries a lower pressure load.
• Perchloroethylene is the quiet one. At 121 °C it has the least vapour pressure of the four (14 mmHg), it is non-combustible, and it is the least likely to create a pressure question at the drum head.

3. Class follows the state, not the name

All four are “chlorinated”, and a buyer who assumes they therefore share a classification is wrong in the first row:

⇒ Practical consequence: an enquiry that asks for “chloromethanes” without naming the product cannot be quoted. The quote has to be built line by line, and the cylinder line is the one that usually changes the freight and the packing certificate.

4. What differs on the document set

5. Segregation: what a mixed container has to answer

The four can travel together only within the segregation rules for their classes — and the class 2.1 cylinder shipment is the constraint in that mix, not the three solvents. Two questions settle it before booking: how the cylinder line is separated from the toxic line, and whether the route’s rules permit the combination at all. Answering “chloromethanes, one container” is not an answer.

FAQ

What are the four chlorinated products, and what is each one’s boiling point? Methyl chloride −24.4 °C, dichloromethane 39.6 °C, chloroform 61.12 °C, perchloroethylene 121 °C.

Why does methyl chloride travel in a cylinder and not a drum? It is a liquefied gas at ambient temperature, so the containment has to be pressure-rated.

Which is class 2.1 and which are class 6.1? Methyl chloride is UN 1063, class 2.1. Dichloromethane (UN 1593), chloroform (UN 1888) and perchloroethylene (UN 1897) are class 6.1, packing group III.

Does the boiling point change the packaging decision for the liquid products? It changes the pressure question inside the drum — dichloromethane is the highest of the three liquids, perchloroethylene the lowest.

Can the four ship together? Only under the segregation rules for their classes; the class 2.1 line is the constraint, and the entry, class and packing group are carried per line on the transport document.

What we can provide

All four products are supplied by the group’s operating companies, quoted by CAS with the assay, the UN entry and class, the packaging and the net weight per unit — with the document set for the route listed on the quotation rather than left to be discovered at the port. Where the destination has a restriction on the product or on the packaging, it is stated before booking.

Who contracts and ships: every shipment is contracted, invoiced and shipped by the group operating company named on the quotation and on the documents for that shipment. This page is the group’s technical reference material.

Related

• Which refrigerants, chloromethanes and electronic specialty gases are supplied — the full scope in one table.
• Dichloromethane specification grade for coatings and adhesives — the DCM line in detail.
• Dangerous goods mixed loading: segregation, UN marks and stacking — how the classes share a container.
• Reading a COA against the specification sheet — how the batch documents are checked at receipt.

Sources

• Methyl chloride — CAS 74-87-3, boiling point −12 °F (−24.4 °C), molecular weight 50.5 (NIOSH Pocket Guide, CDC): https://www.cdc.gov/niosh/npg/npgd0403.html
• Methyl chloride — CAS 74-87-3, UN 1063, transport class 2.1, liquefied gas (ILO/WHO International Chemical Safety Card 0419): https://chemicalsafety.ilo.org/dyn/icsc/showcard.display?p_card_id=0419
• Chloroform — CAS 67-66-3, boiling point 61.12 °C, density 1.484 g/cm³ at 20 °C, vapour density 4.12 (ATSDR Toxicological Profile for Chloroform, CDC): https://www.atsdr.cdc.gov/toxprofiles/tp6-c4.pdf
• Perchloroethylene — CAS 127-18-4, boiling point 250 °F (121 °C), specific gravity 1.62, vapour pressure 14 mmHg, vapour density 5.83 (OSHA Occupational Chemical Database, entry 190): https://www.osha.gov/chemicaldata/190
• Dichloromethane — CAS 75-09-2 (PubChem compound record): https://pubchem.ncbi.nlm.nih.gov/compound/Dichloromethane
• UN 1063 / 1593 / 1888 / 1897 entries and classes (as carried on the transport documents for each product; entries repeated in the manufacturers’ safety data sheets)

Prepared by Hangrui Holdings Limited (Hong Kong) — the group holding company. Shipments are contracted, invoiced and shipped by the group’s operating companies: HARMONY TECHNOLOGY (ZHEJIANG) CO., LTD., QUZHOU HUAFU NEW REFRIGERATION MATERIAL CO., LTD. and RIBOLUO CHEMICALS (ZHEJIANG) CO., LTD. The binding figures for any shipment are those on the specification sheet, the packaging marks and the transport document for that route.