Fire Extinguishers - self inspecting? This from the front of NZS4503:2005
COMPETENT PERSON. Person with the relevant industry training, experience and with access to the requisite tools, equipment, parts and information (including the manufacturer’s installation/service manual) to be capable of carrying out the installation, inspection, maintenance or testing requirements of this Standard. Qualification to an applicable industry training programme recognized by the New Zealand Qualifications Authority is an acceptable means of compliance with this requirement.