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Rapid urbanization increases the number of vehicles on a road section significantly throughout the country. Traffic in India is generally heterogeneous consisting of variety of vehicles which comprise wide range of static and dynamic characteristics. To estimate volume of such heterogeneous traffic it is essential to convert the different types of vehicles into equivalent passenger cars and express the volume in terms of Passenger Car Unit (PCU) per hour. The equivalency unit is universally adopted for measurement of traffic volume and the value is obtained by taking the passenger car as the 'Standard Vehicle.' The present study has been concentrated on four and six lane divided urban arterials in Kolkata. The PCU of vehicles have been presented for both categories of urban roads and the values are found to be higher than the values given in IRC: 106-1990. It has also been observed that, PCU values of different types of vehicles have been found to be different for different ranges of volume, composition and v/c ratio. Mathematical relationships have been developed on the basis of the variation of PCU with traffic stream parameters. The relationships are developed to forecast the PCU for several vehicular categories that have been statistically validated for different ranges of traffic stream parameters. [ABSTRACT FROM AUTHOR]

To optimise surgical outcomes and minimise the risk of infections, effective communication and teamwork are essential in the operating theatre (OT). In this pilot study, we mapped the OT team dynamics and roles in infection and safety-related practices. Between November 2021 and February 2022, data were gathered from adult surgical teams at a tertiary hospital in India. Data included direct ethnographic observations of OT activities and interactions, sociograms of targeted infection and safety-related communication, measurement of OT traffic, and focus group discussions with teams. Qualitative data were coded and analysed using a grounded theory approach. Quantitative data were analysed using descriptive statistics. Data gathered from 51 hours of direct observations across ten surgical pathways include 16 sociograms and 15 traffic-flow maps. Team hierarchies and dynamics are directly influenced by the senior surgeon. The OT staff adhere to implicitly understood roles, creating a missed opportunity for infection-related interventions. Instances of non-verbal communication are common, especially for routine activities. While the surgical and anaesthetic residents and technicians lead most tasks during procedures, the scrub nurse acts as a mediator coordinating and activating tasks among role players across hierarchies. Despite this role, the plan of events is not always communicated to them ahead of the procedure resulting in multiple door openings to source equipment and disposables. Traffic flow, counted by the number of door openings reach up to 14-15 per five minutes, with implications for infection management. Communication around the WHO checklist was limited. While interventions exist to optimise care in the OT, implementation challenges remain. Assigning explicit roles and responsibilities for actioning, including the WHO checklist completion, to specific team members is critical. On reflexive feedback to teams, the visual methods utilised provided an effective means for team reflection and an awareness of practices that may compromise infection management and patient safety. [ABSTRACT FROM AUTHOR]

In India, there is very limited data on vehicular emission characterization in real-world driving conditions and the contribution of non-exhaust vehicular emissions to ambient particulate matter (PM) is still unanswered. Furthermore, there are no real-world emission factors (EFs) for the PM constituents. Thus, this study aims to characterize the trace elements and metals, and black carbon (BC) in PM 2.5 and PM 10 from the light-duty vehicles (LDVs) and mixed vehicular fleet with significant contribution of heavy-duty vehicles (HDVs) through road-tunnel measurements. Real-world EFs were estimated for the measured PM chemical constituents. Further, source apportionment was carried out to find the plausible sources and their contribution to total PM 2.5 and PM 10 road traffic emissions. Air pollutant and traffic measurements were conducted at two roadway tunnels: Eastern Freeway tunnel (FT; only LDVs) and Kamshet-I tunnel (KT; 80% LDVs & 20% HDVs) in Mumbai, India covering both peak and off-peak traffic hours. Major elements (Al, Ca, Fe, K, Mg, and Na) constitute 90─93% of total measured elemental concentrations in both PM 2.5 and PM 10 road traffic emissions. Overall, the elemental concentrations were higher for the HDV-dominant fleet than the LDV-fleet for both PM 2.5 and PM 10. Similarly, BC was higher for the HDV-dominant fleet which is corroborated by the morphological analysis. The measured BC, trace elements and metals EFs in this study were higher than those reported than previous road tunnel studies with similar vehicle composition indicating the presence of high-emitting vehicles in this study. The dominant proportion of PM 2.5 road traffic emissions was from the tailpipe (52%) followed by brake wear (30%) and vehicular driven resuspended road dust (18%). Whilst, resuspended road dust (63%) was identified as the major source of PM 10 traffic emissions followed by vehicular exhaust (28%) and brake wear (9%). With the potential increase in the share of electric and hybrid vehicles in the vehicular fleet, the relative contribution of non-exhaust emissions to the airborne PM will be more significant. Hence, there is an imminent need to regulate non-exhaust vehicular emissions. [Display omitted] • The first study in India to quantify the real-world vehicular PM emission sources. • HDV-constituted fleet dominates the metal and BC concentrations • Measured real-world metal EFs are higher than previously reported studies. • Half of the PM 2.5 road traffic emissions come from non-exhaust sources. • Non-exhaust vehicular emissions are dominant in PM vehicular emissions [ABSTRACT FROM AUTHOR]

A comprehensive understanding of speed-flow-density relations is an essential requirement in planning, design and operation of transportation systems. Many researchers have investigated the nature of speed-flow-density relationships, commonly known as stream models, under homogeneous traffic conditions. However, those models may not be the best under Indian traffic conditions. Indian traffic differs significantly from homogeneous traffic and may need a different treatment for analysis. Not much research has been reported on this important aspect so far from India. The present study is an attempt to develop an optimal traffic stream model suitable for the heterogeneous traffic flow condition existing in India, taking Chennai as a case study. A two-regime speed-density relationship was developed using a conventional optimisation algorithm. Using this, the speed-flow and flow-density relationships were theoretically derived. The results indicate that the proposed model is able to represent the steady-state macroscopic behaviour of the heterogeneous and less lane-disciplined traffic stream under study with reasonable accuracy. [ABSTRACT FROM AUTHOR]

The objective of this study is to develop an empirical noise prediction model for the evaluation of equivalent noise levels (Leq) under interrupted traffic flow conditions. A new factor tendency to blow horn (AH) was introduced in the conventional federal highway administrative noise prediction (FHWA) model and a comparative study was made between FHWA and modified FHWA models to evaluate the best suitability of the model. Monitoring and modeling of Leq were carried out at four selected intersections of Jaipur city. After comparison of the results, it was found that the modified FHWA model could be satisfactorily applied for Indian conditions as it gives acceptable results with a deviation of ±3 dB (A). In addition, statistical analysis of the data comprising measured and estimated values shows a good agreement. Hence, the modified FHWA traffic noise prediction model can be applied to the cities having similar traffic conditions as in Jaipur city. [ABSTRACT FROM AUTHOR]