You are here

What is non-road mobile machinery?

Non-Road Mobile machinery

NRMM is defined as any mobile machine, item of transportable industrial equipment, or vehicle - with or without bodywork - that is:

  • not intended for carrying passengers or goods on the road
  • installed with a combustion engine - either an internal spark ignition (SI) petrol engine, or a compression ignition diesel engine

Examples of non-road mobile machinery include, but are not limited to:

  • garden equipment, such as hedge trimmers and hand-held chainsaws
  • generators
  • bulldozers
  • pumps
  • construction machinery
  • industrial trucks
  • fork lifts
  • mobile cranes

In the UK, the legislation governing emissions produced by engines fitted in NRMM is the Non-Road Mobile Machinery (Emission of Gaseous and Particulate Pollutants) Regulations 1999, as amended. This sets emission standards for carbon monoxide, hydrocarbons, oxides of nitrogen and - for diesel engines - particulate matter.

Engines installed in NRMM are split into categories for spark ignition (SI) and compression ignition (CI), and then further classified according to the engine power rating. These categories are then given limits for specified gaseous output, more commonly known as the engine's 'stage'.

SI engines of up to 19kW net power that are used in land-based portable or mobile machinery are covered by the NRMM regulations.

Variable-speed and fixed-speed CI engines are covered where their rated power is between 18kW and 560kW (equivalent to 24hp to 760hp).

In theoretically perfect combustion, carbon dioxide, water and nitrogen are the end products. In reality the incomplete combustion of diesel fuels results in emissions that include oxides of nitrogen (NOx), carbon monoxide (CO), carbon dioxide (CO2), water (H2O) and unburned hydrocarbons (HC). There are also un-burnt carbon particles, as well as engine oils, debris, soot and ash particulates, known as particulate matter (PM).

NRMM used on any major development in London will be required to meet a new emission standard from September 2015.