ADV - Arbeitsgemeinschaft Deutscher Verkehrsflughäfen:
     "Piktogramme zur Orientierung auf Flughäfen", Stuttgart 1974
AIGA (American Institute of Graphic Arts) and the U.S. Department of Transportation (DOT):
     Signs and Symbols, 1974
British Standards Institution: BS 6034:1990, ISO 7001:1990 Specification for public information symbols
CEN European Committee for Standardization: Procedures for the standardization of graphical symbols:
     ISO/TC 145 - all graphical symbols (Guidance ? Graphical symbols)
China National Standards (GB): GB/T 10001. 2-2002. I*.
      Public information graphical symbols for use on sign
China, Bureau of Technical Supervision (国10号) MH 0005-1997 民用航空公共信息
     (civil aviation public information signs with graphic symbols)
ГОСТ (Государственный стандарт: Euro-Asian Council for Standardization)
     ГОСТ Р 51885-2002 Знаки информационные для общественных мест
     (GOST R 51885-2002 informational signs for public places)
ERCO GmbH; Piktogrammsystem; continually expanded to Otl Aicher's syntactic pictograms;
     Lüdenscheid, Germany
International Organization for Standardization:
     ISO 7001:2007 specifies graphical symbols for the purposes of public information.
International Organization for Standardization:
     ISO 9186-1 u. 2:2007 specifies methods for testing the comprehensibility of graphical symbols.
International Organization for Standardization:
     ISO 22727:2007 specifies requirements for the creation and design of public information symbols.
Massachusetts Port Authority (Massport), Boston (USA):
     Logan International Airport Sign Program Guidelines and Graphic Standards
Normas Portuguesas NP 4280:1995 (1ª Edição) pp.5.
     Segurança contra incêndio. Sinalização de dispositivos de combate a incêndio.
SABS - South African Bureau of Standards: SANS 7001, standardised public information symbols

Federal Aviation Administration: A/C 150/5340-18E, Standards for Airport Sign Systems

Another Elevator pictogram: Shutterstock, stock pictogram