Health impact assessments are the developer's new secret weapon. Here's how they work and why you need one

Many people are familiar with environmental impact assessment (EIA) - the process by which information about the ecological effects of major projects is gathered and evaluated. Health impact assessment (HIA) is much less well known. However, developers and planners are increasingly using HIA to gauge the impact of a proposal on community health - it can be a vital tool in getting local communities on side.

What is HIA?

HIA tends to focus on aspects of a project that can indirectly affect health. These include:

  • Availability, access to and quality of housing
  • Employment opportunities
  • Education and training
  • Transport networks
  • Amenities, recreation and green space
  • Maintenance and enhancement of social capital and cohesion.
HIA has developed from EIA and the movement to promote "healthy" public policy. It is not mandatory, but aims to influence policy and decision-making.

The assessments are based on a range of sources including evidence from public and professional stakeholders, as well as public health and medical knowledge.

What does health mean in this context?

There are two main models of health: the biomedical and the social. The biomedical approach sees health as the absence of disease. It argues that treating identified illness is the best way of improving health and that, if a proposal does not generate measurable illness in individuals or communities, it is likely to enhance health and wellbeing.

However, our health can also be affected by unemployment, low self-esteem or the lack of supportive relationships, as well as by low income, poor education or badly built homes and neighbourhoods. The social model of health argues that these indirect and broader factors have a dominant influence. The impact of a proposal on these determinants needs to be assessed to ensure it enhances individual and community wellbeing.

HIA uses a mixed approach. It recognises the value of measuring the direct impact on physical health. However, it argues that the effects on the wider determinants of health are likely to have the greatest influence.

Who would undertake an HIA?

For formal planning and decision-making processes, there are HIA practitioners in the public and private sectors. For more information, go to the weblink below.

When would you carry it out?

Many developers are concerned an HIA will focus local communities on the downsides of a proposal. The reverse is usually the case

The best time to carry out an HIA is at the design stage. Early-stage analysis provides the best opportunity for modifying the proposal in a cost-effective and timely way.

What does the HIA process involve?

HIA follows a similar process to EIA. There are stages that cover screening (whether to do it), scoping (how to do it) and appraisal; mitigation and enhancement; and options and recommendations. The key difference is that HIA integrates community consultation within the assessment process.

How widely applied are HIAs?

HIA is well established in Europe, North America and Australasia with the UK, Canada and Australia being lead countries in the development of HIA theory and practice. HIA is not a legal obligation in most countries but is increasingly seen as best practice.

What are the advantages?

  • It supports the planning and decision-making process by providing relevant health impact information and analysis
  • It improves proposal design, implementation and operation
  • It increases community support and reduces community concerns
  • It reduces costs and liabilities further down the development cycle
  • It enhances a developer's reputation by demonstrating its commitment to corporate social responsibility
  • It provides cost-effective added value.
Are there any disadvantages?

Many developers and policy-makers are concerned that commissioning an HIA will hinder their proposals because it will focus local communities and decision-makers on the downsides of a proposal.

The reverse is usually the case. Projects can be delayed because the effects on health are not considered early on and have to be assessed later when local communities raise them as a concern.

Good HIA practitioners, and good HIAs, recognise that no proposal is wholly negative or positive. The key is to develop measures that can eliminate or minimise negative impacts and maximise positive ones.

Developers commissioning HIAs demonstrate their commitment to a community's welfare, improve the plan's chances of success and reduce residents' worries by designing out those aspects that could cause concern.