**3.3 Challenges in developing countries in the field of information on environmental noise emissions and guidelines for overcoming them**

At-source measures that reduce overall emissions are preferable to noise exposure measures. For example, for road transport reduction of sound pressure levels of the engines and tyres, traffic management and transport demand management measures are options for reducing emissions at source. For aircraft transport reducing emissions at sources is a major pillar of the Balanced Approach of the International Civil Aviation Organization [41].

This section aims to include and/or strengthen enforceable, affordable, sustainable, and highly effective measures to assess and find solutions to reduce sound emissions and, consequently reduce public exposure to adverse sound pressure levels.

The 'challenges' to achieving this objective include [17]:

	- Emission inventories and quality-assured emission data.
	- Periodical update of emissions standards.
	- Regional harmonization of emissions standards.
	- Low-cost and effective alternative technologies.

'Guidelines' for overcoming main challenges of environmental noise emissions include [16, 19]:

	- On-road and off-road motor vehicles.
	- Railways.
	- Airports and low-flying aircraft (i.e. close to airports).
	- Ships in or close to ports.

*Guidelines for Environmental Noise Management in Developing Countries DOI: http://dx.doi.org/10.5772/intechopen.109952*

	- Tighter emission standards and their enforcement.
	- Low-sound vehicle technology.
	- Inspection programmes.
	- Establishment of maintenance programmes.
	- Improved integrated land use, traffic planning and demand management on a regional scale.
	- Public transport and non-motorized transport.
	- Economic incentives/taxation.
	- Tighter emission standards.
	- Emission control technologies and low-noise production.
	- Land use planning, zoning, and economic restructuring.
	- Enhancing enforcement.
