Greenstock is a well known shatter proofing company that has a variety of options for those in need of this type of item. Requirements vary from applications such as sports halls, where tubes need to be more robust in order to prevent injury should a light be damaged or to food lighting applications. There are various coatings offered by Greenstock, each has their respective uses.
PTNA coating, or Polyethlene Terapthalate in full, is a more economic approach to shatterproofing. it is useful for locations that need to reduce fragmentation in the event of a breakage (for example sports halls or offices). This type of shatter resistance is not IEC 61549 rated, so is NOT suitable for food applications and cannot be used in an enclosed fitting.
FEP coating is a much more premium type of layering. it is IEC 61549 rated and so is suitable for applications such as catering lighting or food lighting. It is also suitable for any type of fitting, be it closed or open.
ECO coating is similar to FEP, but slightly more economical. It is still IEC 61549 rated so is suitable for a wider range of applications however it has a lower melting point thus cannot be used in closed fittings, only open batten type or CAT2 style fittings.