Plastics

Customers are already used to using plastic vessels in some situations, such as nightclubs or festivals. Some polymers can fracture into shards depending on how they are used, stored and cleaned although the injury potential is likely to be less severe than glass.

Field trials using polycarbonate vessels have resulted in dramatically reduced numbers of glassing injuries. However, a problem with polycarbonate is that it breaks down and crazes over time under harsh dishwashing making it less useful for commercial use.

Copolyester glasses provide a balance of properties, including clarity, toughness and durability, and have received favourable feedback from brand owners, designers, manufacturers and consumers. A heavy base can be added to vessels to give a heft close to glass.

In use, copolyester has a similar look to glass and its impact strength and shatter resistance make it less likely than glass to cause injury. The material’s ability to resist heat and harsh detergents means there is no crazing or cracking in commercial dishwashers. It also has good scratch and chip resistance making stacking a viable option.

American research shows that Tritan copolyesters do not affect hormone levels, an issue of concern with some plastics. An advantage for manufacturers is that it has a fast throughput and lower energy requirement as there is no need for annealing. In addition, plastics are less likely to break during transit than glass.

Disposal

Copolyester can be recycled where appropriate streams exist.

Some polymers such as polypropylene and polyethylene have existing waste and recycling streams but most (used as an alternative to glass in drinking vessels) do not have designated waste streams and are collected as 'mixed' plastic.

 Resources

Evaluation of the Lancashire Polycarbonate Glass Pilot Project, a study where glass drinking vessels were replaced with polycarbonate versions. Injury levels were reduced as a result of the replacement.

Banning glassware from nightclubs in Glasgow (Scotland): observed impacts, compliance and patron's views, a study indicating that use of all-plastic drinking vessels results in less injury risk from disorder. Patrons also reported feeling safer in these venues.