POST OCCUPANCY REVIEW LED INSTALLATION

Transcription

1 POST OCCUPANCY EVALUATION POST OCCUPANCY REVIEW LED INSTALLATION May 2012 Job No Baltic Street, Edinburgh EH6 7BW tel: +44 (0) fax: +44 (0)

2 POST OCCUPANCY REVIEW: LED INSTALLATION Contents 1. Introduction 2. Methodology 2.1. Pilot study 2.2. Site selection 2.3. Design of the questionnaire 2.4. Site review 2.5. Carrying out the survey 3. Results 3.1. Site observations and measurements Site location The interior The lighting 3.2. Questionnaire results Personal details Artificial lighting Natural lighting Control Experience of the space 4. Analysis 4.1. Admin staff 4.2. Clinical staff 4.3. General experience of the space 4.4. Limitations 4.5. Improvements 5. Conclusions Bibliography Appendices Appendix 1: Introductory script Appendix 2: Survey questionnaire KSLD

3 POST OCCUPANCY REVIEW LED INSTALLATION 1. Introduction This post occupancy review is intended to give an independent evaluation of a recent lighting installation utilising a large proportion of LED sources for general lighting. The review takes the form of a pilot study, testing a general, non-site specific questionnaire on a small sample of respondents. The review included site observations and physical measurements; and a questionnaire survey of staff based in the building. The site selected was a newly opened private healthcare facility in Manchester. The facility features a large proportion of LED downlights used for ambient lighting, mixed with other typical light sources including T5 fluorescent and compact fluorescent. Having recently come into use, it also provided an opportunity to ask staff about the lighting in comparison to their previous workplaces within a reasonable space of time. This report outlines the methodology used, results gathered and provides some analysis and identification of trends (the small sample size and untested nature of the questionnaire limit any conclusions which can be drawn). 2. Methodology 2.1. Pilot study This post occupancy evaluation was designed as a pilot study, to test a basic questionnaire on a limited sample of respondents, and identify key results or trends to steer further research. The questionnaire focused on the lighting (both natural and artificial) within the building and was intended to explore occupants reactions to an installation with a high proportion of LED sources. The questionnaire was intended to be fit for general use (with a few minor changes) rather than tailored to one specific building/installation. Initial desk-based research, including a review of other building occupancy surveys, was used to inform the design of the questionnaire. The survey was carried out on site with members of staff, and observations of the primary room types recorded. As a pilot study, limitations on any conclusive results or trends are imposed by the small sample group and untested nature of the questionnaire Site selection The healthcare facility was selected as the sample site as it is relatively new and has a range of light sources, including a majority of LEDs providing general ambient lighting. As staff have moved into the building fairly recently, their impressions of the lighting in comparison to previous workplaces are still fresh. The building has a number of different areas within specific functional requirements, which allows the lighting to be assessed across a range of performance criteria. The LED downlights were provided by two manufacturers (each in defined areas), ensuring consistency across output and colour temperature. KSLD

4 2.3. Design of the questionnaire The questionnaire (see appendix 2) has five main sections: the first is a brief section recording basic personal details; the second focuses on the artificial lighting; the third on natural light; the fourth on controls; and the fifth on the overall experience of the space. The four main sections are designed to elicit general responses about overall satisfaction, suitability for normal tasks and ease of use. The format of the answers includes ratings-scales, closed questions and open-ended questions to allow people to comment in their own words. In the first section, respondents were asked to identify the room in which they spent the majority of their working day. Answers in the second, third and fourth sections relate to this primary workspace; with the final fifth section asking respondents to think about the building as a whole Site review Both the site review and questionnaire survey were carried out in a single day, on the 8th March The site review was carried out in the morning, approximately between 10am-12pm. Observations regarding room layouts, finishes, glazing, the artificial lighting, daylight and controls were recorded for each of the key room types (reception and main waiting area; main admin office; corridor; secondary waiting area; boardroom; consulting room; diagnostic room; and patient recovery room). A number of light level readings were taken in each room under typical conditions, including both horizontal and vertical measurements. Photography inside the building was not permitted Carrying out the survey The survey was carried out in person with individual respondents. The interviews took place in the boardroom of the hospital, allowing a degree of privacy. Respondents dropped in to take the survey rather than having an allocated time slot - this was felt to suit the workings of the hospital better. The facilities manager had acted as the key contact for arranging the visit, and had advised staff in advance of the survey date. On the day, he also reminded staff in person about the interviews and encouraged them to take part. On arrival, each respondent was welcomed and asked to sit down. A standard introductory script outlining the nature of the questionnaire was read to each respondent before the survey started (see appendix 1). The actual survey questions were read aloud to the respondent and the answers noted down. Given the pilot study nature of the survey, this was felt to be the best way of securing a full set of answers from each respondent; and allowed the interviewer to skip any irrelevant questions. Each interview took around 10 minutes to complete. In total, 12 people took part in the survey, representing the majority of staff working on the day. They reflected a range of roles, including admin, clinical and facilities staff. The hospital has 23 employees; the sample therefore represents about 50% of staff. KSLD

5 3. Results 3.1. Site observations and measurements Site location The facility is located within a newly built commercial tower to the south of Manchester s city centre. The building is adjacent to a major through-road, on a small development site. The site is open, and the primary building facades face roughly north east and south west (see figure 1). Figure 1: site plan (building outlined in red) The hospital occupies the ground floor of the building with various other organisations occupying the floors above. The major facades are largely glazed. Figure 2: view of the building (taken from the north west corner) [Above left: background image from Google Maps (satellite view), Right: image from Google Maps (street view), ] The interior The main entrance to the hospital is located to the rear of the building, in the centre of the facade. This leads into a large double aspect reception and waiting area. Corridors run out along the central axis in both directions. Consulting and diagnostic rooms open off this corridor, with the main operating theatres located in the south wing. The majority of the consulting and diagnostic rooms, and the main admin office, are to the outside of the building and feature large windows; many of the spaces benefit from large quantities of natural light, and on a bright day feel largely daylit. The finishes are generally light, and the overall interior has a bright, contemporary feel. The majority of the walls throughout have a white paint finish; all areas and rooms have feature walls painted in a brighter colour such as pale yellow, pale green or light aubergine. Floor finishes vary by area and room function, from pale tiles in the public and circulation zones to a pale screed in the medical rooms. Other than the medical equipment in the consulting and diagnostic rooms, the furniture and fittings are domestic in style. KSLD

6 Figure 3: Main reception area (Signage removed from rear wall in Photoshop to maintain anonymity.) Figure 4: Typical corridor area (diagnostic room shown to left of view; small secondary waiting area to centre of view) KSLD

7 Figure 5: Consulting room [Images taken from the facility website, ( )] The lighting The artificial lighting uses a variety of sources and fitting types. The reception and waiting area uses a mixture of LED downlights and decorative compact fluorescent pendants; the main admin office has diffused T5 600mm square ceiling luminaires; while the corridors and diagnostic and consulting rooms are fitted with LED downlights. LED downlights are used throughout. These are of two types: that described as typical in the following sections is a small recessed downlight with white bezel and specular silver reflector, colour temperature 4,000K and colour rendering CRI>80. The second type is used at the main reception and waiting area only: these have a more organic form, with an array source and colour temperature 4,000K. The following tables detail the finishes, lighting and light levels in various key areas. Light levels were all measured on the same day within a 2 hour period in the morning (with the exception of the admin office where readings were taken in the afternoon). Zones corresponding to the measurement areas are marked on the building floor plan, figure 6 below. It was not possible to review any of the surgical theatres. The lighting in the theatres is purely functional, designed for performing operations; and will not be considered further in this report due to its highly specific nature. KSLD

8 Figure 6: Hospital floor plan KSLD

9 Table 1: Main reception and waiting area Room description (finishes, etc): Painted walls, white and pale green finishes. Cream floor tiles. White ceiling. Dark tiled feature wall behind reception desk. Timber fronted reception desk with green top; similar finishes to refreshments counter at side of waiting area. Seating in mix of grey, pale green and orange fabrics; central seating group around a coffee table, with additional seating around the perimeter. Glazing: Glazed at two sides of the space (double aspect). Entrance faces south west; glazed wall at waiting area faces north east. Full height glazing at entry; mostly clear with some frosted panels. Glazing along waiting area runs from approx 900mm from FFL to ceiling height. View from waiting area to front of building: no blinds. View from main entrance across the car parking. No blinds. On a bright day, space feels largely daylit, even in the centre of the space. Artificial lighting: Small organic recessed LED downlights: trimless version with white curved form. LED module seen to be an array of chips rather than single source, as used elsewhere in the building. 3x directional versions to the tiled feature wall. Space generally illuminated by a regular array of the downlights, approx. 15 over the reception area. Accent blue LED strip integrated at skirting level at reception desk. Cluster of decorative pendants over the central seating group at the waiting area: spherical form, in two different sizes; opaque body with soft diffuser at the base, warm white compact fluorescent source. Row of 6x blue LED versions of the organic recessed downlights above the seating along the glazing line. Regular array of 15 white downlights to provide general lighting. Feature linear wall light with colour change element (very slow cycle). Task lighting: None. Controls: Wall control plate behind reception desk (typical 4 button - on full, dimmed, heavily dimmed and off). Light levels: Artificial lighting on full. Bright day, high white clouds and sunlight. Readings taken in the morning. Orientation Illuminance On floor, adjacent to main entrance horizontal 725 lux On drinks / refreshments counter horizontal 318 lux On reception desk counter top horizontal 419 lux On tiled feature wall at reception, at eye level vertical 395 lux On typical wall, at graphic panel, at eye level vertical 215 lux Waiting area, on central coffee table horizontal 770 lux Waiting area, centre of floor horizontal 815 lux KSLD

10 At side seating, at height of face of seated person vertical 960 lux Table 2: Typical corridor Room description (finishes, etc): White painted wall to one side; yellow painted wall on the other. White ceiling. Pale cream floor tiles, matt finish. Artwork at intervals and doorways off to consulting and diagnostic rooms. Glazing: None within view. Artificial lighting: Typical LED downlights down the centreline of the corridor, at approx. 2m spacing. Task lighting: None. Controls: Control plate, located behind the reception desk. Typical 4 button plate - on full, dimmed, heavily dimmed and off. Controlled by reception staff. Light levels: Orientation Illuminance On floor, directly beneath a downlight horizontal 200 lux On floor, midway between downlights horizontal 160 lux On wall, inline with a downlight, at eye level vertical 103 lux On wall, midway between downlights, at eye level vertical 86 lux Table 3: Secondary waiting area Room description (finishes, etc): Pale yellow painted wall finish; pale grey floor tiles. White painted ceiling. Chairs with orange covers. Glazing: None - no windows within view. Artificial lighting: 4x typical small LED downlights. Task lighting: None. Controls: Wall control plate adjacent to entry. Typical plate, 4 button - on full, dimmed, heavily dimmed and off. Light levels: KSLD

11 Orientation Illuminance In centre of floor horizontal 360 lux On chair seat horizontal 330 lux Wall surface vertical 220 lux Table 4: Typical consulting room Room description (finishes, etc): Painted wall finishes: 3 white walls; 1 pale yellow end wall. Pale yellow-grey screed type floor finish. White panel ceiling. Timber topped desk; medical equipment at desk. Wall mounted sink at side of room. Typical ceiling height, m. Glazing: Window, completely covered using a black out blind. No daylight ingress. Artificial lighting: 6x typical small LED downlights, arranged as 2 rows of 3, set slightly towards the long sides of the room. Cause scalloping on the long sides, top of scallop approx 1500mm from FFL. Scallops on end walls higher. Task lighting: None for desk work. Optometry equipment has an integrated directional reflector lamp. Controls: Wall plate adjacent to door. Wireless plate at desk. Both typical, 4 buttons for lighting control plus raise and lower for the blinds. Lighting full on, dimmed, heavily dimmed and off. Light levels: Recorded with full blackout blinds in place; lighting set to full on. Orientation Illuminance On desk, directly below a downlight horizontal 360 lux On floor, in centre of room horizontal 300 lux At sink / handwash area horizontal 290 lux At sink / handwash area vertical 150 lux On headrest at patient s chair vertical 120 lux On artwork at wall vertical 80 lux KSLD

12 Table 5: Typical diagnostic room Room description (finishes, etc): Painted wall finishes: 3 white walls; 1 pale aubergine-purplee wall. Pale yellow-grey screed type floor finish. White panel ceiling. Timber topped consultant s desk with computer screen and keyboard. 2 patient chairs with adjacent narrow desk units at side wall. Cream chairs. Wall mounted sink at side of room. Typical ceiling height, m. Glazing: Window, completely covered using a black out blind. No daylight ingress. Artificial lighting: 6x typical small LED downlights, arranged as 2 rows of 3, set slightly towards the long sides of the room. Cause scalloping on the long sides, top of scallop approx 1500mm from FFL. Task lighting: None. Controls: Wall plate adjacent to door. Wireless plate at desk. Both typical, 4 buttons for lighting control plus raise and lower for the blinds. Lighting full on, dimmed, heavily dimmed and off. Light levels: Recorded with full blackout blinds in place; lighting set to full on. Orientation Illuminance On floor in centre of room horizontal 330 lux On consultant s desk horizontal 360 lux At sink / handwash area horizontal 250 lux At sink / handwash area vertical 123 lux On wall, at eye level (within scallop of light) vertical 85 lux On patient chair at headrest vertical 115 lux Table 6: Patient recovery room (refractive surgery) Room description (finishes, etc): Painted walls; pale yellow end walls, long white wall; opposite long wall mostly glazed. Four patient recovery recliners; dark red colour. Counter unit with fridges and storage underneath along solid long wall. Glazing: One long wall largely fully glazed; from approx. 900mm from FFL to ceiling level. Southerly aspect, view over car parking. White roller blinds at windows, pulled down; gaps between blinds allow considerable daylight ingress and direct sunlight entry. KSLD

13 Artificial lighting: 12x typical small LED downlights, in 2 rows of 6, set towards the long walls of the room. 2x additional typical LED downlights over the servery counter. Task lighting: None. Controls: 2x wall control plates, adjacent to the two entry doors at opposite ends of the room; plus a wireless plate at the servery counter. Wall plates typical lights and blinds control (4 button lighting control plus raise and lower for blinds). Wireless plate for lighting control only. Light levels: Artificial lighting set to full on. Blinds fully drawn but allow significant daylight ingress; bright day outside with direct sunlight. Readings taken in the morning. Orientation Illuminance On servery counter horizontal 615 lux Centre of floor horizontal 500 lux On wall, behind servery counter, at eye level vertical 340 lux On artwork, on end wall, at eye level vertical 215 lux On patient recovery chair, at headrest vertical 170 lux On floor, in direct sunlight horizontal 1150 lux Table 7: Main admin office Room description (finishes, etc): 3 walls painted light green; rear wall white painted. White 600mm square panelled ceiling. Grey carpet to floor. Standard office furniture with desks running around the walls; timber desk tops. Glazing: Windows at end wall running full width; height from approx. 900mm from floor level up to the ceiling. South west facing aspect; open view over the car park to green space beyond. Direct sunlight ingress; significant proportion of view is of the sky. Manually operated roller blinds at windows. Artificial lighting: Array of semi-recessed 600mm square fluorescent fittings. Heavy opal diffuser; 2x T5 lamps. Fully dimmable. Task lighting: None. Controls: Single wall plate at rear of room. Plate with combined lighting and blind control. 4 lighting settings - full on, partially dimmed, heavily dimmed and off. Manual raise and lower buttons for the blinds. KSLD

14 Room description (finishes, etc): 3 walls painted light green; rear wall white painted. White 600mm square panelled ceiling. Grey carpet to floor. Standard office furniture with desks running around the walls; timber desk tops. Light levels: Readings taken with blinds up (i.e. not in use); bright day with weak sunlight; artificial lighting on. Time of day: afternoon. Orientation Illuminance Centre of floor (in weak sunlight) horizontal 1534 lux Desk surface at rear of room horizontal 691 lux Desk surface in front of window (in weak sunlight) horizontal 5170 lux Wall surface near window (at eye level, standing) vertical 3110 lux Wall surface at rear of room (at eye level, standing) vertical 500 lux Table 8: Boardroom Room description (finishes, etc): Walls with paint finish; white, with one pale green wall. White 600mm square panelled ceiling. Grey carpet to floor. Large central conference table, timber top; six chairs, orange fabric. Glazing: Windows along short end wall, from about 900mm to ceiling level. Outlook to the front of the building, north east aspect. Electric roller blinds operated from the control plates. Artificial lighting: 10x typical small LED downlights: 6 no. in two rows over the conference table; plus 4 no. along the main display wall to light an artwork. Task lighting: None. Controls: Wall plate adjacent to door plus wireless plate on table. Typical 4 button lighting control plus raise and lower for the blinds. Light levels: Bright day outside, readings taken in the morning. Lighting on at full. Orientation Illuminance On table, in front of typical seating position horizontal 625 lux On painting, on display wall vertical 420 lux On floor at entry horizontal 335 lux KSLD

15 3.2. Questionnaire results Section 1: personal details Table 9 below outlines the personal details provided by respondents in the first section of the questionnaire. The majority of respondents were female (10 of 12); with a fairly even split between clinical and admin roles. All admin staff were based in the main admin office, while clinical staff worked across various consulting and diagnostic rooms and the theatre. Table 9: Respondent details Respondent Gender (male / female) Age (years) Role Primary workspace Glasses or contact lenses (yes / no) R1 M >50 Facilities manager Throughout the building Y R2 F >50 Admin Admin office N R3 F <30 Admin Admin office N R4 F Admin Admin office N R5 F Clinical Theatre N R6 F Clinical Consulting room N R7 F Admin Admin office N R8 M >50 Clinical Diagnostic room Y R9 F Clinical Diagnostic room Y R10 F <30 Admin Admin office N R11 F Clinical Theatre N R12 F <30 Housekeeping Throughout the building N Section 2: artificial lighting Section 2 considered the artificial lighting in the primary workspace each respondent identified in the first section of the questionnaire. All 12 respondents felt the room was well lit; and that the lighting was suitable for the tasks that they usually had to carry out. 2 people identified that they had no desk lamp and would like one for reading, etc. Table 10 below details the answers provided on the ratings scales. KSLD

16 Table 10: Section 2 results Question Low value (=1) Results (range of answers and average) High value (=7) Average Median 2.1 How satisfied are you with the lighting overall? unsatisfied very satisfied In your room, is there... too much light too little light For clinical staff For admin staff Do you ever find the light fittings themselves too bright? yes, causes discomfort no, not at all For clinical staff For admin staff Are you satisfied with the way colours look under the light? 2.7. What do you feel about the colour appearance of the light itself? unsatisfied very satisfied too warm too cool Comments R1: its fairly neutral, blends with the area [facilities manager]. R3: its not bright white - it does not make pages of white paper feel very bright [admin]. R10: it can look a little bit clinical but is better when dimmed [admin] Section 3: natural lighting Section 3 considered the natural lighting in each respondent s primary workspace. 7 people received natural light in their main workspace, with 5 receiving no natural light at all. Of the 5 staff working in fully enclosed or blacked-out rooms, 4 were clinical staff, with 2 working mainly in theatre, and 2 based in diagnostic rooms. In these cases, blackout conditions were considered appropriate for the nature of the room and the tasks. In all cases where a room received natural light, it was also able to receive direct sunlight ingress. Of the 4 people who stated a preference for working under natural light alone (figure 7), 3 currently work in areas with no natural light at all - this result might therefore represent a knee jerk reaction against their current conditions rather than a more considered view. KSLD

17 Figure 7: Responses to question 3.4 Do you prefer working under artificial lighting only, natural light only or a mixture of both? Table 11: Section 3 results Question Low value (=1) Results (range of answers and average) High value (=7) Average Median 3.2 In your room, too much too little is there too much or too little natural light? (9 responses) Notes: 3 of the clinical staff who work under blackout conditions answered as not applicable - a lack of natural light being totally appropriate for the nature of the work and space, whatever they might prefer personally. 3.3 If sunlight can enter your room, do you ever find this too bright for comfort? (7 responses) 3.5 If the room has both artificial and natural light, how well do you think these work together? (7 responses) yes, causes discomfort don t work well at all no, not at all For admin staff (5 responses of 7) work well together For admin staff (5 responses of 7) KSLD

18 Question Low value (=1) Results (range of answers and average) High value (=7) Average Median 3.6 Compared to your previous workplaces, is the amount of natural light Additional comments about natural light in the building... much worse much better Comments: R1: room has no daylight but nature of the job allows frequent movement throughout the bldg [facilities manager]. R2: previous room had no window and was oppressive [admin]. R3: previous workplace was a large building with a deep floorplate, so little natural light [admin]. R4: was previously in a mobile operating theatre where theree was very little natural light [clinical]. R5: all theatres should be blackout so total lack is appropriate to the tasks [clinical]. R7: was in theatre before where there is no natural light [clinical]. R8: room has no natural light [clinical]. Comments: R1: all rooms have blinds so it is easy to control the natural light [facilities manager]. R2: daylight in own room works because there are blinds and the lightingg can be dimmed. Generally, the building has lots of windows and maximises the use of daylight quite well. There are no blinds in the reception area (not sure why). This area gets sun in the evening so this can be a problem [admin]. R3: in the office, the shiny desk surfaces mean you have to pull the blinds if it's sunny; also to let you see the computer screen. There are no blinds in reception. It can get too bright near the window in summer [in the main waiting area]- it's not good if the waiting area is busy and people do not have a choice of where to sit [admin]. R6: in the consulting rooms - the natural light is fine for staff, but not for patients: it reflects ontoo the test charts they have to read (charts displayed on flat screens rather than paper). The blinds have been changed to blackout blinds to get around this [clinical]. R9: the lighting is appropriate to the function of the hospital [clinical]. R11: fantastic, lots of windows [clinical] Section 4: control Section 4 considered the control of both the natural and artificial lighting in each respondent s workspace. As can be seen in figure 8 below, almost all (11 of 12) respondents had controls in their room. The only one without (R1) has a temporary office set up within a room originally intended as a storage area, with the lighting controlled via motion sensor. KSLD

19 Figure 8: Control of artificial light Table 12: Comparative control of artificial light Question Low value (=1) Results (range of answers and average) High value (=7) Average Median 4.4 Compared to your previous workplaces, is the level of control that you have over the lighting... much worse much better Comments: R1: no wheree else has had dimming facilities [facilities manager]. R2: the step dimming [3 levels] is too abrupt, the step changes are too great. Gradual dimming would be better. [admin] R3: much better - previous workplace had no individual control, the lighting was controlled by a building management system [admin]. R4: much better - previous place was on/off only, it did not have dimming [admin]. R5: much better - the stepped dimming is good to have. Previously it has been on/off only [clinical]. R10: the dimming is good [admin]. R11: previously had a rotary dimmer system with gradual dimming. But the stepped dimming is good enough [clinical]. All rooms with windows have blinds. In the consulting and diagnostic rooms and other medical areas these are full electrical blackout blinds, with control via the wall plates. In the admin areas and more relaxed post-treatment rooms, the blinds are electrical roller blinds, again controlled via the wall plates. KSLD

20 The only area with no blinds is the main waiting area. Of the 7 people with windows in their workspace, all were happy with the method and level of daylight control Section 5: experience of the space The final section in the questionnaire considered people s experience of the space as a whole, rather than just their own room. Figure 9 below indicates which words were thought to best describe the overall feel of the lighting (respondents were asked to select a maximum of three from the list). Figure 9: Lighting descriptors The next series of questions asked respondents to consider the overall facility in comparison to previous workplaces. Table 13: Comparison to previous workplaces Question Low value (=1) Results (range of answers and average) High value (=7) Average Median 5.2 In general, do you feel the lighting here is more or less satisfactory than in your previous workplaces? less satisfactory more satisfactory Comments: R1: The level of control is different here [previously worked in an industrial environment, facilities]. R9: The artificial lighting is a lot better [clinical]. KSLD

21 Question Low value (=1) Results (range of answers and average) High value (=7) Average Median 5.3 Compared to your previous workplace/s, is there anything that you particularly like about the lighting here? 5.4 Is there anything that you particularly dislike? Comments: R1: the LEDs - long life, less maintenance [facilities manager]. R2: the lighting has obviously been thought about with patients and staff in mind; it's flexible and allows different settings [admin]. R3: the control. Also that it's not too bright - the fittings in the office are diffused, it gives a smoother light. [Previous workplace had direct downlights, admin]. R4: the control [admin]. R5: the amount of natural light in the building [clinical]. R6: the lack of glare; and the lack of dark and light pools (the even-ness of the lighting) [clinical]. R7: like the control [admin]. R8: the ability to control it [clinical]. R9: like the control panels [clinical]. R10: the controls and the dimming. There is plenty of natural light [admin]. R11: more daylight, more windows. Right balance between natural and artificial lighting [clinical]. R12: like the ability to dim up and down to suit yourself [housekeeping]. All respondents answered no to this question. Figure 10: Graph illustrating answers to question 5.5 Have you ever suffered from dry eyes, eye fatigue, blurry vision, eye strain or headaches? Question 5.5 elicited answers on eye-related health and wellbeing, illustrated by figure 10 above. Of the answers given, 6 people reported no change (whether suffering or not) between this building and previous workplaces. Of the 6 people who had experienced a change, 4 now suffer where they did not in previous workplaces. Of these, 2 had undergone laser eye surgery since moving to the building, a KSLD

22 known side effect of which is dry eyes; a third now has a diagnosed medical condition which causes eye problems. Overall, 5 people reported suffering from dry eyes in the building, with 2 of these linking it to the air conditioning system (which is felt to be very effective as is suitable for a healthcare facility, and to make the air noticeably dry). Table 14: Final comments Question 5.6 Have any of your patients or visitors ever commented on the lighting here? 5.7 Do you know what type of light sources (type of lamps) are used in this building? 5.8 Any final comments? Comments R7: people like the blue lighting in the waiting area - it's relaxing. People also like the linear wall light, it changes colour so it s a bit of a feature [admin]. R1: LED, fluorescent (of various different types), compact fluorescents [facilities]. R3: no - believes it to be LED but is not sure [admin]. R11: in the theatre - xenon lamp in the microscope [clinical]. R3: [the line of blue downlights in the waiting area along he glazing line] postsurgery, the blue light can be too much for patients and it makes them squint [admin]. R7: overall thinks it's really good; well lit and well maintained [admin]. R8: the blue lighting in the window at the waiting area makes patients look weird - it would have been better to have a warmer colour [clinical]. KSLD

23 4. Analysis 4.1. Admin staff The five admin staff who took part in the survey work together in the main admin office, an open-plan office just off the reception area. The office has large, roughly south facing windows, with the desks arranged around the perimeter, facing the walls. Artificial lighting is provided by an array of square T5 fittings, partially recessed, with heavy opal diffusers. Roller blinds and the lighting are controlled from a wall plate (raise and lower for the blinds; three levels of dimming for the lighting). As a group, the admin staff were satisfied with the lighting overall; the average figure inclines light levels marginally towards too much, but the median figure is centrally placed at about right. The fittings themselves were felt to be verging on too bright and causing discomfort; but that the dimming system controlled this when it became an issue. Facing south, the office receives plenty of natural light and direct sunlight; this was generally perceived to be positive, as the blinds and lighting system allowed this to be controlled - it was clear from comments made by all admin staff that they change the blinds and lighting settings on a regular basis throughout the day to maintain comfortable lighting conditions. All were positive about the level of control provided. The nature of the open plan environment may be influencing the results. For example, if one member of staff was more sensitive to bright light, vocalised this on a regular basis, and adjusted the lighting accordingly, it would raise awareness of the potential issue in the other staff members and acclimatise them to different light levels. Observations of the T5 diffused ceiling fittings at full output did not record them as noticeably over-bright or glaring; although working on screen-based tasks under the fittings for extended periods of time could clearly give a different perspective. Direct sun and daylight ingress posed a more obvious problem on the day of the site review, with particularly high light levels recorded near the windows (>5000 lux) Clinical staff Five clinical staff took part in the survey; two based mainly in theatre; two based in diagnostic rooms and one in a consulting room. As discussed earlier, the theatre lighting is not being specifically considered in this report. The diagnostic and consulting rooms have similar layouts, and are lit by six typical recessed LED downlights, laid out as two rows of three. All clinical rooms with windows are fitted with black-out blinds. The blinds and lighting are operated via wall control plate and matching wireless plate (raise and lower for the blinds; three levels of dimming plus off for the lighting). Overall, clinical staff had a high level of satisfaction with the lighting, with the light levels provided about right. Unlike the admin staff (who sit under T5 fittings), no clinical staff reported finding the LED downlights too bright. All clinical staff regularly used the control plates, switching or dimming the lighting being important for carrying out tests and examinations; all stated this control as being essential to their role. With four of the five clinical staff working under full black-out conditions, it was difficult for respondents to comment on whether a room had too much or too little natural light - black-out conditions being the norm and appropriate for the nature of the tasks (in theatre and diagnostic rooms), even if their personal preference might be to have some natural light. Comparison to previous workplaces was also difficult for this reason. Three of the four respondents who expressed a preference for working under natural light only currently work in fully blacked-out clinical areas; this reaction may reflect a reaction against the full black-out rather a genuine preference for totally daylit conditions. KSLD

24 The member of staff based in the consulting room (R6) indicated that the blackout blinds in these rooms had been installed as the natural light had previously created veiling reflections on test panels, causing problems for patients undertaking reading tests. While the blinds could be easily operated using the control plates, the impression was given that the blinds are generally now left closed most of the time General experience of the space The final section of the questionnaire considered respondents experience of the facility as a whole, rather than their primary workspace. In selecting words which best described the feel of the lighting, welcoming, comfortable and cheerful (chosen 10, 9 and 7 times respectively) were felt to reflect the overall impression of the space: all are positive whilst also fairly neutral. Clinical was selected 5 times: the term was used in a more positive way than perhaps the general public might use it. Business-like and homely were both selected only once; with stark receiving no votes. Overall, the lighting was felt to create a positive, professional impression; and was appropriate to the function of the building. All respondents felt the lighting was more satisfactory than in previous workplaces. 8 of the 12 respondents picked out the controls as being an aspect they particularly liked; with 3 noting the amount of natural light as being especially good. With no respondents highlighting any aspect they disliked, clearly the lighting installation has been generally well received. The only specific element which was referenced by several people was the line of blue downlights at the main waiting area. One respondent stated that visitors liked these, finding them relaxing; another felt it made patients look weird and that a warmer colour would have been better. A third respondent noted that, post-surgery, the blue light could be too much for patients and made them squint; this respondent was not clinical staff therefore this comment should be treated with care. In all cases, the blue lighting was seen as different enough to warrant comment - no comments were made about the general lighting in the hospital. This indicates that a good quality LED lighting installation does not draw extra attention and is experienced by the general public as similar to one using more traditional light sources: at a basic level, it is satisfactory enough not to be noticed Limitations Limitations on the reliability of the results are imposed by the small sample size of just 12 respondents (although as 50% of the overall workforce they may be taken as fairly representative). Many of the staff are based in more than one area and move throughout the building on a regular basis. This means that they do not sit under one lighting condition for extended periods of time. This may skew the results in a more favourable direction, as problems tend to be become more apparent or less tolerable over time. The nature of the building as a healthcare facility could also have produced some generally irregular results: for example, a total lack of natural light in a workspace would not usually be considered acceptable but was felt to be appropriate and therefore acceptable given the nature of the tasks to be performed in the diagnostic rooms and theatres. The large areas of glazing in many of the spaces, and the generally daylit feel to the rooms utilising the windows may have made it difficult for respondents to judge the artificial lighting in these areas. Conversely, the rooms with blackout facility enable the artificial lighting to be judged solely on it s own merits. While the lighting in the diagnostic and consulting rooms and corridors utilised LED sources, the lighting in the other areas used mixed sources: T5 fluorescent lamps in the admin offices and a mixture of LED KSLD

25 and compact fluorescent in the main reception/waiting area. In moving through the building, respondents would therefore be under a range of sources (including daylight) rather than solely LED. This makes it difficult to draw any clear conclusions about the LED sources alone. While care had been taken to use normal language rather than technical terms in the questionnaire, a small number of the respondents did not have good English and were unclear as to the meaning of a few of the questions Improvements Improvements to the design of the questionnaire could be made by some restructuring, for example so that control was dealt with next to the artificial and natural lighting sections, rather than being in a separate section. Respondents tended to think of each aspect of the lighting as including the control, so this would help reduce any repetition in the responses. Respondents did not generally have any additional comments to make to the open ended questions. Reducing these to a minimum (perhaps one at the end of each section) to capture any additional comments; and replacing them with fixed choice or ratings scales, where appropriate, might help gain more useful information. Carrying out the survey with a greater number of respondents would obviously be preferable. Selecting a site with less variety between areas, less variety in light sources, and less daylight may also assist in gaining more definitive reactions to the LED sources. There is the option for the questionnaire to be formatted as an e-questionnaire with respondents completing their own answers; the e-questionnaire would need to be tested on a small sample group first. The major issue with this technique is that a significant proportion of the sample group may have issues with completing the whole questionnaire on screen. As respondents are not dealing with a live interviewer the likelihood of deliberately false or misleading answers increases, as lying to a machine does not have the social resistance that lying to another person has. Equally, people might be more likely to discuss the questions with colleagues and have their answers influenced by their peer group. Undertaking the survey with a large sample group in face-to-face interviews would be time consuming but is felt to offer the most reliable method of gaining full and accurate information. In the case of carrying out a full size questionnaire survey, the site review would have to be carried out in advance to ensure all questions were relevant to the site, e.g. in this survey the large proportion of blacked-out rooms made a number of the questions in the daylight and control sections less relevant to some of the respondents questioned. Performing the site review in advance would also allow any special features or conditions which might impact on the results to be identified, and referenced in the questionnaire where appropriate. 5. Conclusions Given the limitations discussed above, it is difficult to draw any definitive conclusions. However, the results seem to indicate that good quality LED sources are no more or less acceptable to building occupiers that other good quality, more typical, light sources. The sample group felt that having a good level of control over the lighting, and individual access to such controls, was important - i.e. that being able to control the lighting was more important [to them] than what the lighting actually was. Access to daylight controls was also of particular importance to the sample group: to clinical staff as their daily tasks necessitate black-out conditions; and to admin staff as their workspace is subject to considerable sunlight ingress, which needs controlled to remain comfortable and KSLD

26 prevent glare. Overall, this indicates that access to adequate controls is of more important to people than the actual lighting, provided the lighting is of a generally acceptable standard. In terms of the pilot study itself, the review has demonstrated that the questionnaire process as trialled, with the amendments outlined above, will be a successful way to gather post occupancy feedback. Test sites are needed that offer both a larger sample group, and ideally a less varied environment, where the experience of working under LED sources is less diluted either by daylight or other light sources. Analysis of the results needs to be informed by the site survey, the weather conditions on the day and at the time of the survey, and by the working or operating practices of the building occupants. Coherent presentation of the results is a significant challenge given the many variables, especially with a small sample group. KSLD

27 BIBLIOGRAPHY Bordass, Bill, and Leaman, Adrian. Making feedback and post-occupancy evaluation routine 1: A portfolio of feedback techniques. Building Research & Information, 2005; 33(4): Bordass, Bill, and Leaman, Adrian. Making feedback and post-occupancy evaluation routine 3: Case studies of the use of techniques in the feedback portfolio. Building Research & Information, 2005; 33(4): Bordass, W., Leaman, A. and Eley, J. A guide to feedback and post-occupancy evaluation. The Usuable Buildings Trust [ Brawley, Elizabeth C. Enriching lighting design. NeuroRehabilitation, 2009; 25: Fotios, S. A. Chromatic adaptation and the relationship between lamp spectrum and brightness. Lighting Research & Technology, 2006; 38-1: Fotios, Steve. Lighting in offices: lamp spectrum and brightness. Colouration Technology, 2011; 127: de Kort, Y. A. W. and Smolders, K. C. H. J. Effects of dynamic lighting on office workers: First results of a field study with monthly alternating settings. Lighting Research & Technology, 2010; 42: Maloney, Laurence T., Gerhard, Holly E., Boyaci, Huseyin and Doerschner, Katya. Surface colour perception and light field estimation in 3D scenes. Vision in 3D Environments, 2010; Cambridge University Press. Thomas, Leena E. Evaluating design strategies, performance and occupant satisfaction: a low carbon office refurbishment. Building Research & Information, 2010; 38(6): The Usuable Buildings Trust. The Building Use Studies (BUS) Occupant Survey: Origins and Approach Q&A [document provided by Adrian Leaman of the Usable Buildings Trust]. The Usuable Buildings Trust and BSRIA. The Soft Landings Framework for better briefing, design, handover and building performance in use [ Viliunas, V., Vaitkevicius, H., Stanikunas, R., Svegzda, A., and Bliznikas, Z. LED-based metameric light sources: Rendering the colours of objects and other colour quality criteria. Lighting Research & Technology, 2011; 43: KSLD

28 APPENDICES Appendix 1: Introductory Script KSLD

29 POST OCCUPANCY EVALUATION Introduction I work for a design consultancy. I am here today to carry out a post-occupancy evaluation of this facility. I should make it clear that my company was not involved in either the design or fit-out of the building. We have been commissioned to carry out an independent, impartial review. The questionnaire should take around 10 minutes to complete. I will read the questions to you and fill in your answers. The responses are a mixture of single choice options, rating scales and open-ended questions. All information provided during the interview will be treated as anonymous. The results will be compiled for a report for the company that commissioned us, and may be used for further research and presentation purposes. Do you have any questions before we start?

30 Appendix 2: Survey Questionnaire KSLD

31 POST OCCUPANCY EVALUATION Ref. no. 1. Personal details Gender: male female Age: under over 50 Do you wear glasses / contact lenses? yes no Role: clinical admin other Where do you spend the majority of your working day? If other, please specify: Reception Diagnostic room Admin office Theatre Consulting room Other If other, please specify: 2. Artificial lighting Thinking about the place you selected, where you spend most of your working day: 2.1. How satisfied are you with the lighting overall? On a scale of 1 to 7, where 1 is unsatisfied and 7 is very satisfied. unsatisfied very satisfied 2.2. Do you feel the room is well lit? yes no Comments: 2.3. Is the lighting suitable for the tasks that you usually carry out? yes no Comments:

32 2.4. In your room, thinking about the artificial lighting, is there: On a scale of 1 to 7, where 1 is too much light and 7 is too little light. too much light too little light 2.5. Do you ever find the light fittings themselves too bright? On a scale of 1 to 7, where 1 is no, not at all and 7 is yes, causes discomfort no, not at all causes discomfort 2.6. Are you satisfied with the way colours look under the light? For example, the appearance of human skin-tones under the light, and how natural people look. On a scale of 1 to 7, where 1 is very satisfied and 7 is unsatisfied very satisfied unsatisfied Comments: 2.7. How do you feel about the colour appearance of the light itself? i.e. how warm or cool the lighting appears. On a scale of 1 to 7, where 1 is too warm and 7 is too cool too warm too cool Comments: 3. Natural light Still thinking about the room where you spend most of your working day, but this time looking at natural light: 3.1. Does the room receive natural light? yes no 3.2. Is there too much or too little natural light? On a scale of 1 to 7, where 1 is too much light and 7 is too little light. too much light too little light