Specification for red and green filters used in ophthalmic dichromatic and dissociation tests Ingestion-build-50790 1 has been corrected

1 has been corrected

intended to be connected to public low-voltage distribution systems of between 220 V and 250 V line to neutral at 50 Hz

BS 3988 was first published in 1966 under the authority of the Non-ferrous Metals Industry Standards Committee and at the request of the Aluminium Industry in view of the increasing use of aluminium for electrical conductors of many types

BS ISO 4254-9 does not apply to:

Manufacturers of belt drives and pulleys

Specification for red and green filters used in ophthalmic dichromatic and dissociation tests Ingestion-build-50790 1 has been corrected1 Scope This British Standard specifies requirements for red and green filters of glass or plastics materials used in ophthalmic tests as follows: a) dichromatic tests for ametropia, and b) dissociating the eyes in various tests of binocular co operation.