Central Pollution Control Board

Any inspection and maintenance programmee requires a considerable amount of investment not only to setup facilities but also for comprehensive tests throughout the year. Various types of I&M programmes are being followed the world over. Many countries prioritise control of emissions while others aim to control both emissions and road accidents. Instances of public-private-partnership (PPP) in setting up I&M facilities is also common in many countries. Management, efficient and reliable operation of the I&M programmes is a priority issue in selection of any I&M programmes and networks. This section describes some I&M network types or I&M implementation structure types:

Centralised type of I&M network is usually based on limited numbers of large high volume test sites and are primarily managed by a single entity either a state government agency or an approved private contractor, whereas a decentralized type has large numbers of test sites with the infrastructure and ability of only catering to a limited number of vehicles and are usually run by car dealers, service stations, etc. However, cities like Mexico has centralised test centers managed by large industrial firms. Some aspects of both the types of networks are given in the Table-1 below:

Table-1: Comparision of Centralised Vs. Decentralised System

Items	Centralised	Decentralised
No. of cenetrs	Few	Large
Improper Inspection	Low	High
Inspection cost	Low	High
Skill competence	High	Low
Satisfaction	High	Low
Control	Easy	Difficult
User convenience	Low	High
Waiting period	More	Less

Test-only centers are such centers where only inspection tests are carried out and the centers are not permitted to undertake any repair works. These types of centers are usually the centralized types. These centers are cost effective in the long run and are believed to perform tests efficiently but may result in long waiting periods least the centers are improperly designed. Whereas, test & repair centers are those, which have the permit to carry out both inspection and the repairs of the non-compliant vehicles. Most of the decentralized type centers are usually test & repair centers. Test & repair centers may be convenient for the vehicle users but tendency of fraud and abuse exists. There also exist another type of network called the Hybrid centers which are combination of both test-only and test & repair centers. These are also usually decentralized.