This may be why there's a shortage of diesel heaters.
From a motorhome forum via the T6 forum.
"Suffolk Trading Standards Imports Surveillance Team have detained 973 diesel heaters at the Port of Felixstowe over the last two months. All products were found to be unsafe, with listings for all sellers removed on eBay.
Consignments arrived at the Port in October and November and were stopped by the team, with samples sent to a test house for assessment.
Each of the products did not meet the requirements of the Supply of Machinery (Safety) Regulations 2008 because they could present hazards of fire and death due to poor supporting installation information.
Manuals supplied with the products failed to give measurements for installation and did not give the minimum distance the exhaust pipe should be installed from flammable material or material that could give off poisonous fumes when heated, such as insulation material.
If installed incorrectly, no warning was provided about heat and dangers to the user.
Large parts of the manuals were written in poor English and used the wrong words. The intended meaning was, in some cases, difficult to understand.
Additionally, the products and instructions did not have the name and address of the importer or manufacturer and did not include the required Declaration of Conformity (DoC). A DoC is a formal declaration by a manufacturer or the manufacturer's representative that the product to which it applies meets all relevant requirements of all product safety directives applicable to that product.
If you have purchased a product that you think may be unsafe, stop using it immediately and report it to Trading Standards via Citizens Advice Consumer Service on 0808 223 1133."