The story of PSPA, Brightness classification standard for long afterglow luminescent materials and long afterglow luminescent pigments

The story of PSPA Brightness classification standard for long afterglow luminescent materials and long afterglow luminescent pigments

The PSPA (Photoluminescent Safety Products Association) is an association that, amongst other activities, recommends acceptable levels of performance for photoluminescent material in the industry.

The PSPA defines their class standards in accordance with the methodology set out in the commonly used standard of DIN 67510 pt 1 and ISO 17398 whereby luminance is measured following a specific level of excitation and then calculation made to the threshold of visibility which is 0.32mcd/m2.

It is the current recommendation of the PSPA that PSPA class A luminance be achieved as a minimum. More recent recommendations and new standards indicate that class B performance should be the minimum acceptable level and the recent Fire Regulatory Reform Act re-enforces this. Furthermore, it is worth noting that for some time now the PSPA have been discussing their own current recommendation and it is now decided that class A will be phased out and the minimum recommendation is to be PSPA class B for all applications.

The industry has spent a lot of time discussing standards in the recent past and many existing standards are part way through a review period. There are also other international standards which require specific performance, some being required at differing levels of excitation. Please contact us if you require any further performance data. Of particular note at the moment is the ISO 23601 Safety Identification – Escape Plan Signs which actually specifies a PSPA class C material as being the required photometric performance level.

PSPA performance classification when tested according to DIN67510 Pt 1

Figures in MilliCandella per Square Metre unless specified (mcd/m2)

PSPA Class

2 minutes

10 minutes

30 minutes

60 minutes

To 0.32mcd/m2

Minutes at lest

Class A






Class B






Class C






Class D






BS ISO 17398

Safety colours and safety signs – Classification, performance and durability of safety signs.

BS ISO 16069

Graphical symbols – Safety signs – Safety way guidance systems (SWGS)

DIN 67 510 Part 4

The Internationally recognised German standard for the luminance performance requirements for photoluminescent materials

DIN 67 510 Part 1

Definitions of test methods for luminance performance.

IMO resolution 752(18)

Guidelines for the evaluation, testing and application of low location lighting on ships

Photoluminescent Safety Products Association / Photoluminescent Safety Association guide to the use of photoluminescent egress marking in stairwells

New York City Local Law 26


Post time: Oct-27-2021