Background In 1993 The Delhi government made it mandatory for all MTW riders to wear helmets and use of seatbelts for front seat passengers of cars in 2002. It became compulsory for all cars in 2002 to be equipped with seatbelts in the rear seats, but not their use. In 1999 helmet use was made optional for female MTW riders and the notification was reversed in September 2014 and helmet use became mandatory for all MTW riders again. In this paper we report the motorcycle helmet and car seat belt use patterns in Delhi, India, and the implications for effectiveness of traffic safety interventions.

Methods In September 2014 we conducted roadside traffic surveys at 17 locations and observed 3,251 MTWs and 3,200 cars. All surveys were done between 0700 and 1900 hours. The following data were recorded: Number and sex of passengers by their location in the vehicle, seatbelt use by car occupants and helmet use by MTW occupants. The data are analysed for estimating the effectiveness helmet and seatbelt laws and the outcome in terms of lives saved.

Results MTW use patterns: Total MTW: 3251; Passengers per MTW: 1.3; Children per 100 MTW: 3; Overall helmet wearing rate: 88%; Driver helmet wearing rate: 96%; Pillion helmet wearing rate: 70%.

Car use patterns: Total Cars: 3,200; Passengers per car: 2.0; Overall belt use 60.3%; Driver belt use: 91.5%; Front seat passenger belt use: 76%, Rear seat passenger belt use: 6%.

Fatality rate estimates per billion vehicle-km in Indian cities: Delhi: Car-3.8, MTW – 16.5; Average for 5 other Indian metropolitan cities where helmet laws are not enforced and seat belt law enforcement is weak: Car – 12.5, MTW – 37.7.

Conclusions Helmet wearing rates for MTW riders exceeds 88% in Delhi where the law is enforced as compared to less than 20% in other Indian cities where the law is not enforced. Between the years 1999 and 2014 helmet use by women passengers was insignificant, but increased to more than 70% immediately after the mandatory law was reintroduced. Belt use by front seat car passengers in Delhi is 76%. This shows that publicity campaigns do not result in high belt and helmet use, but enforcement of mandatory laws has a very strong effect on compliance.

Fatality rates per billion vehicle km in Delhi for cars are 30% of those in other cities and for MTW 44%. The lower rates in Delhi are probably partly due to enforcement of helmet and seatbelt use laws.