Safety case principles for high-rise residential buildings

Following the Grenfell Tower fire in June 2017 and the Independent Review of Building Regulations and Safety undertaken by Dame Judith Hackitt, the Government’s response (in the form of the Building Safety Bill (the Bill)), has now reached Parliament.

The Bill

Under the Bill, new duties are proposed for those responsible for the safety of high-rise buildings. The proposals may yet be subject to change but are intended to apply only to England.

The draft provisions are aimed at fire prevention and at reducing the severity of serious fires or structural failures imposing more stringent requirements for certain types of residential buildings. Residential buildings will fall within the scope of the Bill if they are at least 18 metres in height or they are at least seven storeys tall and contain at least two residential units. This might therefore include multi use buildings with residential dwellings. The Bill proposes changes to the way high-rise residential buildings are managed and includes a ‘safety case’ regime for these buildings.

HSE response

The Health and Safety Executive (HSE) has published its early key messages in its document entitled, “Safety case principles for high-rise residential buildings”.

The HSE documents comment upon some of the potential changes to help those who are likely to be affected by the Bill. For those responsible for the management and operation of buildings in scope, a risk-based, sensible and proportionate approach is required to ensure the safety of the people who live in and use those buildings. HSE recommends that preparations for the new laws coming into effect are commenced now.

The safety case regime aims to make sure that buildings in scope are safely designed and constructed, are of a good standard and are operated and managed in a way that protects people from the spread of fire or structural failure, therefore reducing the severity of a serious incident.

Who the changes will affect?

Under the proposals, people who manage or are responsible for high-rise residential buildings will have to take all reasonable steps to make sure their buildings are safe.  They will be required to put together a ‘safety case’ and also to produce a ‘safety case report’.

People with these responsibilities will need to demonstrate proportionately and effectively how they are keeping their buildings safe, explain why they believe the measures they have in place to prevent and limit the consequences of a major accident in their building are sufficient and effective and be able to demonstrate that they have a robust approach to the ongoing management of the building to make sure that those measures remain effective and up to date.

HSE explains that these responsibilities can be met by owning and managing the risks associated with the particular building.  This is achieved by identifying potentially harmful events and showing that the necessary measures are in place to prevent, control and mitigate those risks.

Identifying major accident hazards in buildings

The proposals deal with ‘major accident hazards’, in other words incidents likely to involve multiple injuries or deaths or serious damage to property.

HSE believes that a systematic review of the particular building will be required so that an understanding is gained of what could go wrong and how significant the impact could be. For high-rise residential buildings, analysis of two broad categories of hazard is required; spread of fire and structural failure. Such analysis would need to consider any major accident hazard relating to fire or structural failure that has, for example, the potential to impact the safety of occupants of more than one floor and has the potential to impact upon the surrounding population.

What is a “safety case”?

The safety case’s role is primarily to help manage the major accident hazards or serious structural issues of the building. The safety case comprises all the information used to manage the risk of fire spread and the structural safety of the particular building.

What is a “safety case report”?

This is a document that details the safety case. This report should identify the major fire and structural hazards associated with a particular building. It should explain how these risks are managed and what is being done, as far as can be, to prevent a major accident. It should demonstrate how the measures taken are effective in managing and controlling the risk of a major accident. It should be the subject of periodic and event-based review (e.g. following refurbishment) and should contain information such as plans, operational management information and realistic assessment of the potential hazards and mitigating steps taken to address these risks.

The building, its particular hazards and how they are managed, will change over time and the safety case and safety case report will both need to evolve to reflect these changes. Once the safety case regime is operational, the safety case report will have to be provided to the Building Safety Regulator (BSR).

What should the safety case report contain?

Identification of relevant hazards is key. Steps and plans to reduce these hazards should also be included. The report should identify what measures are in place to manage, control and mitigate the risks from those hazards. It should comment upon how these measures are maintained, what checks are done to make sure these measures will work when they are needed and how the safety case will be kept up to date.

HSE recommends that the following are considered and included in the report (note this is not an exhaustive list):

1. Provide a clear description of the building

• What is the building and what features does it contain?
• Describe its use, occupation, density and services provided.
• Identify the key people with responsibility for the building’s safety.
• Describe any other relevant safety information e.g. areas where flammable materials are stored, comment upon vulnerability of certain residents and their ability to evacuate etc.

2. Consider what could be the major accidents involving fire spread and structural safety in the particular building?

• Ask what could go wrong, how could it go wrong and how significant the impact could be?
• HSE points out that existing assessments such as the fire risk assessment may not consider major accidents in enough detail or scope. A more detailed hazard identification of the building focusing on the major accidents may be required.

3. What measures are already in place to prevent and minimise major fire and structural accidents?

• Consider what measures are in place (e.g. fire compartmentation, fire protection for front doors of flats, carbon monoxide warning systems and evacuation plans).
• Consider whether there are enough measures in place for each of the identified major accident hazards and whether there any other reasonable steps that could be taken.

4. How to make sure safety measures will work when required

• Consider the sufficiency of existing systems, procedures, preventative maintenance, instructions, training and supervision.
• Consider whether these measures and the existing safety management system are enough to ensure the safety of the building users from major accident hazards. 
• Ask what further proportionate and effective steps could be taken to prevent, control and mitigate the spread of fire and structural failure?

5. What is your plan to implement any further measures?

• Be in a position to describe why you believe you have done enough to protect people from a major accident and what more you have to do if there are still areas of weakness in the building.

6. Has the purpose of the safety case report been met?

• Demonstrate a good understanding of risk and the measures required to minimise the chance of the identified risks causing serious harm or damage.
• Ensure that adequate and sufficient management systems are in place and ensure you have engaged with the right people e.g. residents, designers, and surveyors.
• HSE advises to ask two questions: can the building safety risks be identified in your building? Can you show how you manage these on an ongoing basis, as far as you can, so that it is safe?

How to prepare

HSE recommends that each particular building is considered in terms of the management of its safety and how you plan to demonstrate to the Building Safety Regulator that steps taken are sufficient and adequate. HSE is keen to point out that existing arrangements may not be sufficient (e.g. the existing fire risk assessment). HSE suggests that existing information about the building is gathered, that the scenarios for fire spread and structural failure are considered and also that the operating or managing organisation is itself considered in terms of the competence of people who work there and what will have to be changed for the new regime.