Abstract
Aim: The objective of this article is to present delays in the standardisation of smoke alarm devices in relation to the present technological advancement of such devices, and to identify errors and irregularities in draft prEN 14604 standard. In addition, the project aims at proposing directions for the quantitative evaluation of a number of parameters of smoke alarm devices.
Introduction: The article presents a brief history of the development of smoke alarm devices (from the first type 710 ionisation smoke detector to ASD-10QR miniature autonomous smoke detector and Nest Protect multi-sensor detector), along with the history of the relevant international standards (from the first ISO 12239 to draft rEN 14604:2016).
Methodology: The main principles of the draft standard prEN 14604, which differ from those present in the currently binding EN 14604:2005, are discussed. Attention is drawn to the unacceptable use of various terms for one concept in the reference standard. Technical errors in images are demonstrated. The content of specific clauses of the standard is suggested, along with the proposed addition of quantitative parameters for the technical requirements for smoke alarm devices. A method of checking the mechanism of sensitivity fluctuation compensation in smoke alarm devices is proposed by retaining a high stability and the necessary rate of optical air density rise in a limited volume.
Results: The abbreviation SAD (Smoke Alarm Devices) is proposed and used in the entire text. Errors in figures included in Annexes G and I are demonstrated, and the new wording of Clause 3.1.6 is proposed. A suggestion is also made to introduce changes to Clause 4.2.1.1 and 4.2.1.5, along with adding a new content to Clause 3.1.7. Evidence proving the non-equivalence of response value and sensitivity is presented. The possibility of creating a station for checking the mechanism of sensitivity fluctuation compensation in smoke alarm devices is indicated. The necessity of introducing the quantitative evaluation of the forces impacting on the device components is confirmed, in order to make the study results unambiguous. Finally, the need to change the technical requirements for wall-mounting smoke alarm devices is indicated.
Conclusions: Taking into consideration the proposed changes to the European and national standards will make it possible to develop standards which will be unambiguously interpreted during smoke alarm device tests carried out in research laboratories and in production environment. Key words: prEN 14604, smoke alarm devices, requirements for optional functions, sensitivity fluctuation compensation
Keywords: prEN 14604, smoke alarm devices, requirements for optional functions, sensitivity fluctuation compensation
Type of article: review article