Technical Justification for

Transcription

1 ECOGLO INTERNATIONAL LIMITED Technical Justification for To meet the Exit Signage Requirements of NCC 2016 EP4.2 For the most current solution documents refer to: (from the Home Page select Technical then Code Compliance) V17.1

2 Introduction This document examines NCC 2016 Performance Requirement EP4.2 of the BCA and demonstrates how Ecoglo photoluminescent signs can be used to meet NCC 2016 via the following methodology: The signs are of suitable size and sufficient brightness to be clearly visible; Charging requirements can be prescribed to ensure the signs can be charged to maintain adequate brightness for sufficient time to allow safe evacuation of the building as per the requirements of EP4.2; The signs can be suitably positioned to identify the location of exits; Ecoglo manufactures photoluminescent sign material to different grades of brightness. Although S14 grade can be used to meet Deemed to Satisfy (DtS) Provisions of Specification E4.8, any reference to Ecoglo signs in this document means Ecoglo S20 grade photoluminescent signs. Performance Requirements are the mandatory requirements of the code and specify the minimum level of performance for all buildings. A Performance Requirement can be satisfied through a Performance Solution or a Deemed-to-Satisfy (DtS) Solution or a combination of both. A Performance Solution is defined as any solution that can meet the Performance Requirements, other than a DtS Solution. A Performance Solution may differ in whole or in part from the DtS Provisions, but will still meet the Performance Requirements as long as it can be successfully demonstrated how this will be achieved. A Deemed-to-Satisfy Solution uses the DtS Provisions and any referenced documents contained within the NCC. These provisions include prescriptive examples of materials, products, design factors, construction and installation methods, which if followed in full, are deemed to comply with the Performance Requirements of the NCC. Performance Requirement EP4.2 specifies To facilitate evacuation, suitable signs or other means of identification must to the degree necessary- (a) be provided to identify the location of exits; and (b) guide occupants to exits; and (c) be clearly visible to occupants; and (d) operate in the event of a power failure of the main lighting system for sufficient time for occupants to safely evacuate. 1

3 NCC 2016 A1.7 (b) clarifies what is meant by the degree necessary - A reference in a Performance Requirement of the BCA to the degree necessary means that consideration of all the criteria referred to in the Performance Requirement will determine the outcome appropriate to the circumstances. These words have been inserted to indicate that in certain situations it may not be necessary to incorporate any specific measures to meet the Performance Requirements. Sufficient time, while not defined, can be taken to mean enough time in particular or given circumstances and/or environments. For example, in a building where occupants have undergone an induction which includes familiarity with evacuation routes and in which trial evacuations are regularly performed, the evacuation time can be expected to be less than that required in a building where there may be many occupants unfamiliar with the layout of the building and its evacuation route. Similarly, the size and type of building, number of occupants, and hours of occupancy all need to be taken into consideration when determining a sufficient time for occupants to safely evacuate. E4.8 NCC E4.8 Design and Operation of Exit Signs DtS Provisions states that every required exit sign must be clearly visible at all times when the building is occupied by any person having the right of legal entry to the building. Required means required to satisfy a Performance Requirement or a DtS Provision of the BCA as appropriate. Exit means (a) Any, or any combination of the following if they provide egress to a road or open space (i) An internal or external stairway. (ii) A ramp. (iii) A fire-isolated passageway. (iv) A doorway opening to a road or open space. (b) A horizontal exit or a fire-isolated passageway leading to a horizontal exit. NCC Specification E4.8 further lists the DtS Provisions for Photoluminescent Exit Signs. Size and brightness of Ecoglo signs to ensure they are clearly visible The two critical aspects to consider to ensure visibility of an exit sign are the size of the sign, and how bright it is. photoluminescent signs. The following table gives the dimensions for Ecoglo signs with 16m and 24m maximum viewing distance. Sign sizes NCC 2016 Specification E4.8 details the sizes and viewing distances required of 2

4 Ecoglo Sign Code Viewing Type Width (mm) Height (mm) Text/Picto Distance Height* (mm) S20-RM m 16m Pictogram S20-RM2916HV-16m 16m Pictogram S20-RML m 16m Pictogram S20-RMR2916HV-16m 16m Pictogram DSS20-RMD m 16m Pictogram S20-RMRL m 16m Pictogram S20-RMRL2916HV-16m 16m Pictogram DSS20-RMRL m 16m Pictogram DSS20-RMRL2916HV-16m 16m Pictogram S20-RM m 24m Pictogram S20-RM4223HV-24m 24m Pictogram S20-RML m 24m Pictogram S20-RMR m 24m Pictogram DSS20-RMD m 24m Pictogram S20-RMRL m 24m Pictogram S20-RMRL4223HV-24m 24m Pictogram DSS20-RMRL m 24m Pictogram DSS20-RMRL4223HV-24m 24m Pictogram *As per the requirements of Specification E4.8 pictorial elements on Ecoglo photoluminescent exit signs are 30% larger than sizes specified in AS AS Emergency Escape Luminaires and Exit Signs uses linear scaling. Ecoglo also manufactures signs in sizes to meet viewing distances of 32m, 40m and 48m. However, for signs with maximum viewing distances greater than 24 metres a Performance Solution must be provided as Specification E4.8 excludes the use of photoluminescent signs for viewing distances greater than 24m. Linear scaling 1, based on maintaining the same subtended visual solid angle across the pictogram elements in the signs, is used to justify the dimensions of Ecoglo signage for viewing distances greater than 24m. Sign brightness During normal lighting conditions the luminance (brightness) of photoluminescent signs is proportional to the illuminance on the sign face from ambient light. During failure of the main lighting, the luminance of photoluminescent signs depends on the brightness and length of time that the previous ambient ( charging ) light has been charging the signs, and also the time since the main lighting has failed. Providing suitable illumination on the face of each photoluminescent sign ensures the signs remain clearly visible during normal occupation, as well as providing sufficient charging to ensure the photoluminescent glow provides suitable visibility after a power failure has caused the loss of all normal lighting. If an exit sign is required in a location where there is insufficient illumination for any reason, a photoluminescent sign will not be appropriate unless a suitable dedicated light source is also installed. During failure of the main lighting Specification E4.8 specifies a minimum luminance of 30mcd/m 2 for not less than 90 minutes for photoluminescent exit signs. NATA accredited luminance testing of Ecoglo S20 Series was performed by Queensland University of Technology (QUT) in April 2014 (see Appendix A). Representative samples of S20 grade material were 3

5 tested in accordance with ASTM E Standard Test Method for Photopic Luminance of Photoluminescent (Phosphorescent) Markings except the activation illumination in clause 8.3 was replaced with 54 lux. Samples exposed to an illumination of 54 lux for 1 hour using a lamp of CCT 4000K gave a reading of 38mcd/m 2 after 90 minutes which well exceeds the E4.8 requirement. However, visibility (legibility) of any specific sign will depend on variables such as contrast (how opaque the background colour is), variations in the text or pictogram, such as size, edge sharpness and stroke width. Ecoglo pictogam exit signs have been tested in accordance with UL 924 Standard for Safety Emergency Lighting and Power Equipment by an independent laboratory to show that they are visible 2 from 24 metres after 90 minutes of darkness (See Appendix B). The independent test also verifies that the pictogram signs are visible from 24 metres when emitting a luminance of 21.4 mcd/m 2. Charging Requirements Specification E4.8 DtS provision requires a minimum of 100 lux at the face of the sign by a dedicated light source with a colour temperature not less than 4000 K. Indoor Charging Indoor spaces are either lit by electric lighting only, or by daylight when sufficient, or supplemented by electric lighting when daylight is not sufficient. Daylight through window glass, whether direct or reflected off room surfaces, provides effective charging for Ecoglo signs. Types of electric lighting that are suitable for charging Ecoglo Exit signs Ecoglo testing (see Appendix C) has verified that fluorescent, metal halide, or LED lighting with a colour temperature of 4000K or greater are all suitable charging sources for Ecoglo exit signage. If the installed lighting in a building has a colour temperature of less than 4000K, a specific design by Ecoglo is required. Illumination The DtS Design Level required of PL Exit signs is that they provide a minimum luminance of 30 mcd/m 2 for not less than 90 minutes in the event of a power failure. Testing performed on Ecoglo exit signs has shown that to reach the Design Level after the sign is completely discharged 3, the following charging is required: 20 minutes with 100 lux on the sign 2 UL 924 defines visible as legible (pertains to text) and distinguishable from other text or symbols. This satisfies the wording clearly visible in both EP4.2 and E To completely discharge, the Ecoglo sign is kept in total darkness for a period of 3 days at a minimum temperature of 20 C. Designing Solutions to meet EP4.2 The scenario below illustrates how the above test result can be used as a starting point for designing solutions to meet Performance Requirement EP4.2. Scenario: The sign has been in total darkness and is fully discharged. If 100 lux is provided on the face of the sign, it will take 20 minutes to reach Design Level. In this situation an operating procedure ensuring 100 lux is on the face of the sign 20 minutes prior to occupation of the building is required. This is a DtS Solution. 4

6 Suitable positions to identify the locations of exits EP4.2 states that suitable signs must be provided to identify the location of exits and guide occupants to exits, while E4.8 defines an exit as any, or any combination of the following if they provide egress to a road or open space: an internal or external stairway; a ramp; a fire-isolated passageway; a doorway opening to a road or open space; or, a horizontal exit or a fire-isolated passageway leading to a horizontal exit. A Performance Solution will be deemed to meet EP4.2 as long as exit signs are located in all positions required by DtS clause E4.5 Exit Signs. (d) door serving as, or forming part of,a required exit in a storey required to be provided with emergency lighting in accordance with E4.2. AS stipulates that exit signs shall be mounted not less than 2m and not more than 2.7 m above floor level, or immediately above the doorway if the doorway is higher than 2.7m. The purpose of this is to ensure that each exit sign is within the field of view of a person with the applicable viewing distance and looking at the relevant door or along the relevant exit path. E4.5 states that an exit sign must be clearly visible to persons approaching the exit, and must be installed on, above or adjacent to each (a) door providing direct egress from a storey to (i) an enclosed stairway, passageway or ramp serving as a required exit; and (ii) an external stairway, passageway or ramp serving as a required exit; and (iii) an external access balcony leading to a required exit; and (b) (c) door from an enclosed stairway, passageway or ramp at every level of discharge to a road or open space; and horizontal exit; and Note: Smoke can readily obliterate even very bright signs, so another important aspect to also consider is mounting a sign as low as possible in a room so it has least chance of being obscured by smoke. It follows that signs that are mounted high up are more likely to be obscured by smoke than signs mounted lower down. See Designers Guide for High Risk Smoke Areas in Technical section on website ( The practicality of installation of electrical exit signs means that they are often mounted at, or just below, ceiling height. However, there are no such restrictions for photoluminescent signs, which can readily be installed low down and on many types of surface, including glazing. ** Outdoor charging, higher charging illuminance, shorter evacuation time and lower luminance visibility, while not currently described in this document, are all factors which can be considered when designing a performance solution to meet the requirements of EP4.2. Contact Ecoglo for more details. Conclusion The above has shown that: Ecoglo signs are of suitable size and can be sufficiently bright to be clearly visible; Charging requirements can be prescribed to ensure the signs can be charged to maintain adequate brightness for sufficient time to allow safe evacuation of the building as per the requirements of EP4.2; The signs can be suitably positioned to identify the location of exits. In this way Ecoglo photoluminescent signs can be used to meet the requirements of EP4.2. ** 5

7 Appendix A 6

8 Appendix A 7

9 Appendix A 8

10 Appendix A 9

11 Appendix A 10

12 Appendix A 11

13 Appendix A 12

14 Appendix A 13

15 Appendix B 14

16 Appendix B 15

17 Appendix B 16

18 Appendix B 17

19 Appendix B 18

20 Appendix B 19

21 Appendix C Ecoglo test report data (Various lamp types) Test No. Date Lamp Type Charging Lux Charging Luminance after 30 Time (min) Minutes (mcd/m 2 ) e502 17/05/12 Fluoro 4000K e503 29/05/12 Led 4000K e507 22/06/12 Fluoro 6500K e508 26/02/12 Met Hal 4000K e548 28/05/13 LED 4000K

22 ECOGLO INTERNATIONAL LIMITED Phone: info@ecoglo.com