Risk Assessing of Glass as a Construction Product

What should we consider when applying glass into our construction projects?

We asked @James Allen, Glass Safety Risk Assessor at AITCo Consulting and Director at the Institute of Construction Management (ICM) in the UK.

James Allen, Glass Safety Risk Assessor at AITCo Consulting and Director at the Institute of Construction Management (ICM)

Since March 2021, Cobuilder and ICM have been collaborating to deliver a structured approach to identifying, assessing, and eliminating hazard risks related to the use of glass in construction projects. The goal of the project is to enable actors to prevent hazardous instances already in the design phase and secure a positive outcome of the hazard audit of the built asset. Through structured digital data, stakeholders will be able to gain access and take full advantage of essential product information, which allows them to adopt a more comprehensive approach to hazard management.

In a special interview for Cobuilder, Mr. Allen shares insights into glass technology, explains why some of today’s practices can put people’s safety at risk and discusses the role of better information management to address such issues.

Glass as a Crucial Building Component

Float glass! Pilkington Brothers’ 1950’s float glass development fuelled a UK and worldwide glazing revolution. This industry-changing process guaranteed a continuous flow of annealed glass with flat and parallel surfaces, vastly reduced imperfections and improved clarity.

Float glass, combining with new silicone sealant, spawned construction glazing dispensing with traditional framing systems. Buildings could be cloaked, internally and externally, with glass units bonded to each other.

In London, commercial premises were always restricted in height by weight considerations in respect of the local clay substrate. Fully glazed high-rise premises now span the range of governmental, local authority, commercial, industrial, educational, recreational and housing sectors.

Cobuilder: Glass as a construction material is everywhere around us. Are there cases when it is not safe to use?

James Allen: Annealed glass remains the base material for producing toughened and laminated grades. Despite its versatility, all glass is fragile to a greater or lesser degree and must always be seen as a potential risk for security or physical safety.

Each glass type must be fitted in the right place to ensure personal safety. Competent risk assessment is indispensable for selection of the best glass, or for recommending use of alternative materials.

The recent horrific Grenfell tower tragedy has pulled the issue of fire safety to the forefront of public awareness. But we ignore inherent danger from accelerating glass installation, so often undertaken without adequate control or close supervision.

The emotive sight of shattered glass heaped in the streets after a bomb blast might be daunting, but UK blast casualties cannot match the daily toll of unreported injury inflicted by breaking or falling glass.

Based on years of observation, glass without consistent supervision should be classed as an unsafe construction material. Concern for a building’s safety and security must be paramount – for employees, visitors, maintenance staff and even those just walking past outside.

Cobuilder: Has the United Kingdom government taken steps to improve glass safety?

James Allen: Unprotected or unmodified annealed flat glass panes, whether used as windows and or as construction cladding, need to be regarded as a potential risk to personal and public safety.

Key to any regulatory control of glass is addressing the chasm between glass installed as part of a construction project and those changes in basic safety created by residents moving into the premises and arranging layout to suit their particular needs.

An empty shell meeting theoretical safety requirements is one thing. But the same premises with tables, desks and chairs set close to low-level glazing require more stringent supervision.

There has been much regulation since 1981 and a rash of non-mandatory British Standards. These only attempt to ensure flat glass safety from manufacture through to installation.

BS6262:1982 Code of Practice for glazing for buildings, together with a separate BS impact testing schedule, was elevated to full UK legal status following a decision within the 1981 the Rimmer v Liverpool City Council Appeal Court judgement.

Glass protection is eroded by loose wording, which allows glass suppliers or installers too much latitude over-interpreting ‘safety’.

Building Regulations can be vague and are sometimes said to leak like a sieve. Happily, for public safety, Building Regulation 7 does have clear safety requirements where glass is the material used and can’t be ignored. On top of this, there are mandatory Health and Safety requirements in the form of Regulations 13 &14 of The Workplace (Health, Safety and Welfare) Regulations 1992.

British Standards are useful guides, albeit with high commercial industry input. Such standards must still pursue strictly objective goals if vital public confidence is to be maintained.

Following the Grenfell fiasco, root and branch reassessment of both regulation and industry standards should be undertaken.

Cobuilder: Does any construction material improve glass safety?

James Allen: Wider use of toughened and laminated glass has had considerable positive effect, even though these materials have their own negative aspects and need to be specified with care.

Window films can be most effective by retaining glass fragments in the face of physical collision, manual assault or blast impact.

However, the quality of window film being used is vital. AITCo insists that only proven material from a reliable source be fitted. The crucial factor dominating quality of window film installation is a professional fitting technique under draconian supervision.

Window film needs regular cleaning, with annual Inspections, if safe retention of broken or flying glass is to be achieved.

Cobuilder: Is there a single problem which needs to be addressed to improve the relationship between people and glass?

James Allen: No single item, but some factors do need addressing:

a) project competence from the initial design, through tendering, construction, handover and population of the premises, with ongoing maintenance and inspection to eventual demolition.

b) supervision and checking at each stage of the construction process, which runs on into the maintenance and aftercare under para a) above.

c) bridging any glass safety information gap between differing needs of the construction phase and those of an incoming client’s non-construction personnel. The latter are forced to live and work daily with the installed glass far into the future.

d) professional risk assessment of installed glass is rare and most duty holders are unaware of its existence. Risk assessment is a combination of art and science. The latter can be taught, but the former is elusive. Risk assessment demands a ‘nose’ for isolating situations of potential danger.

Cobuilder: Tell us how you foresee Data Templates resolving those issues related to glass safety.

James Allen: It all comes down to competent information and data. Improving information management means improving decision
making. It all needs to be linked closely together and available.

Manufacturers control their product information for everybody’s safety. This should be made available to all construction actors working with the materials. Architects, designers, installers and even the client must have access to fully competent product data – this is just what Data Templates aim to achieve.

Additionally, designers and specifiers will become more aware of those materials they intend to use, which will lead to better decisions. Responsibility should not be passed on to building control or to the next actors within the chain.

This negative culture of passing responsibility on to somebody else must be rooted out. Total transparency is of key importance.

It’s a domino effect. If manufacturers fail to share fully all of their product information, then installation of their materials might well be compromised.

Using Data Templates, processes throughout a construction supply chain are improved and performance maximised.

Manufacturers will structure product information consistently and clearly. Properties of the different types of glass may be easily evaluated. Only glass possessing the right properties will be selected by specifiers, designers and even the client. This process of continuous planned control will improve safety
throughout the construction project. It is pivotal that product information can be tracked fully and accurately at any point in the construction processes. If necessary, we should be capable of jumping back to the start of the material’s production process.

On behalf of Cobuilder, we would like to thank Mr. James Allen for sharing his insights about the glass industry. It was really exciting to learn more about one of today’s most commonly used construction products and how digitised Data Templates might bring a whole range of numerous improvements to the total value chain.

If you would like to learn more about Cobuilder’s Data Templatemethodology and how we apply it in our software solutions, feel free to contact us.