A-60 Window

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A-60 windows and side scuttles Outline Specification== Background: ==

According to the current SOLAS requirements, all new tankers are required to have A-60 certified windows (or side scuttles) in the superstructure facing the cargo area plus 3 m. on the sides. This requirement does not include the wheelhouse as yet.*)

Type certification of A-60 windows covers the fire-technical certification of A-60 windows aspects only. In other words, a type certified A-60 window is not necessarily suitable as an external window on a tanker. It is safe to claim that most of these windows are not at all suitable. It is important to keep in mind that the windows need to be equal in mechanical strength to standard windows and side scuttles acc. to ISO norms. Windows, which are relying on spacers between the toughened safety glass and the fire-protection, are likely to fail when exposed to heavy seas (Dwg 3501089). Consequently, the window will be pushed in and will leak. A trading tanker will often be subjected to rough seas but hopefully not subject to fire.

Furthermore, the Fire Protection Code (FTP) issued by IMO, requires testing acc. to IMO Res. A-754 (18) conducted (as a minimum) from the High Risk Side. On a tanker, the HRS has been determined as the external side. An external A-60 window is not symmetric. Consequently, it makes a big difference to the test results if the windows are tested from the external side as opposed to the internal side. The classification societies has not always stated in their type certificates, which way the test was conducted.

A-60 windows, unless efficiently protected against UV-rays, will be discoloured over time. This process is gradual but is a real problem. US Coast Guard , in their role as Port State Control, has required several A-60 windows to be replaced for this reason. All of these windows have been of Gel types as opposed to laminated type.

[edit] Outline specification

Where A-60 windows are to be installed the following criteria shall be met:

• The windows shall have relevant type approval acc. to IMO Res. A754 (18) based upon fire test against the high risk side.
  
• A-60 windows are listed under MED Directive 96/98 EC. For delivery to EU-countries certificates acc. to module B and D, E or F is a requirement.
  
• The windows shall have toughened safety glass dimensioned as per ISO 3254 and ISO 1095 (side scuttles).
  
• The windows shall have mechanical strength as required by ISO 3903 and ISO 1751(side scuttles).
  
• A-60 windows where the mechanical strength is relying on spacers between the different layers of glass, is not acceptable.
  
• A-60 windows shall be efficiently protected against UV-rays by UV-stop film.
  

[edit] Additional comments:

• ) When the latest amendment to Solas was approved, their intention was to include the wheelhouse. The rationale was that the wheelhouse was the ship’s control station in the event of a fire. An efficient fire protection was thus wanted. The reason the wheelhouse was exempted at the last minute was negative experience in optical quality on A-60 windows based upon Gel-based fire protection. Consequently, the navigational requirements could not be met. Meanwhile, more experience has been gained. It is now common knowledge that the requirements for fire-protection and navigation can be met if windows of laminated types are used as opposed to Gel-based windows. One can thus safely assume the rules to be amended to include A-60 windows for the wheelhouse. The only company so far that provides a optical guarantee and a pressure guarantee (as of 28.03.2007) is TeamTec AS in Tvedestrand, Norway. Who allso provides H-120 and A-0 rated windows with an approved optic.