INTERNATIONAL STANDARDS FOR THE INDOOR ENVIRONMENT Where are we and do they apply Worldwide. Professor Bjarne W. Olesen, PhD Fellow, Treasurer

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1 INTERNATIONAL STANDARDS FOR THE INDOOR ENVIRONMENT Where are we and do they apply Worldwide Professor Bjarne W. Olesen, PhD Fellow, Treasurer Technical University of Denmark INDOOR ENVIRONMENT THERMAL AIR QUALITY ACOUSTIC LIGHT

2 EVALUATION OF THE INDOOR ENVIRONMENT DESIGN LEVEL COMMISSIONING TESTING COMPLAINTS STANDARDS ISO EN Ergonomics of the thermal environment Analytical determination and interpretation of thermal comfort using calculation of the PMV and PPD indices and local thermal comfort effects. ASHRAE Thermal environment conditions for human occupancy ASHRAE 62.1 and Ventilation and indoor air quality EN15251 ( EN ) Indoor environmental input parameters for design and assessment of energy performance of buildings- addressing indoor air quality, thermal environment, lighting and acoustic EN Ventilation for non-residential buildings - performance requirements for ventilation and room-conditioning systems

3 International Standards Indoor Environmental Quality pren and ISO DIS 17772: Indoor environmental input parameters for the design and assessment of energy performance of buildings. DTR and ISO DTR 17772: Guideline for using indoor environmental input parameters for the design and assessment of energy performance of buildings. THERMAL ENVIRONMENT ISO EN Principles and application of international standards ISO EN Definitions, symbols and units ISO EN 7730 Moderate thermal environments: determination of PMV and PPD indices and specification of the conditions for thermal comfort. ISO EN 7933 Hot environments: analytical determination and interpretation of thermal stress using calculation of required sweat rate ISO EN 7243 Hot environments: estimation of the heat stress on working man, based on the WBGT index (wet bulb globe temperature) ISO TR Evaluation of cold environments: determination of required clothing insulation (IREQ) ISO EN 8996 Determination of metabolic rate ISO EN 9920 Estimation of the thermal insulation and evaporative resistance of a clothing ensemble ISO EN 7726 Instruments and methods for measuring physical quantities (under revision) ISO EN Assessment of the influence of the thermal environment using subjective judgement scales. ISO 9886 Evaluation of thermal strain by physiological measurements ISO DIS Medical supervision of individuals exposed to extreme hot or cold environments ISO CD Application of international standards for people with special requirements ISO NP Method for the assessment of human responses to contact with surfaces Part 1 Hot surfaces Part 2 Moderate surfaces Part 3 Cold surfaces ISO NP Risk of stress or discomfort in thermal working environments ISO/NP Evaluation of the thermal environment in vehicles

4 Human Heat Balance M-W-E res -C res -E = (t sk - t cl )/ I cl = R+C t sk =Mean skin temperature t cl =Mean clothing surface temperature M =Metabolic heat production W =Mechanical work R =Radiant heat exchange C =Convective heat exchange E =Evaporative heat exchange from skin E res =Evaporative heat exchange from respiration C res =Convective heat exchange from respiration

5 MODERATE ENVIRONMENTS GENERAL THERMAL COMFORT PMV / PPD, OPERATIVE TEMPERATURE LOCAL THERMAL DISCOMFORT Radiant temperature asymmetry Draught Vertical air temperature difference Floor surface temperature Operative temperature Mean value of air and mean radiant temperature C = h c A (t cl - t a ) R = h r A (t cl - t r ) t o = (h c t a + h r t r ) / (h r + h c ) Low air velocity h r = h c t o = (t a + t r ) / 2 so

6 GENERAL THERMAL COMFORT Personal factors Clothing Activity Environmental factors Air temperature Mean radiant temperature Air velocity Humidity PMV 0,303e 0,036M 0,028 3 M W 3, ,99 M W pa 0,42 M W 5 1,7 10 M 5867 pa 0,0014M 34 ta ,96 10 f t 273 t 273 f h t t cl cl r cl c cl a 58,15 PMV-index where t 35,7 0,028 M W cl I 3,96 10 f t 273 t 273 f h t t cl cl cl r cl cl cl a h c = 2,38 t 0, 25 cl ta for 0,25 2,38 tcl ta 12, 1 v ar f cl 12,1 v for 2,38 t cl ta 12, 1 var = ar 1,00 1,290I cl =... for 1,05 0,545I cl = for I cl I cl 0,25 0,078m² KW 0,078m² KW 1 1 PMV = Predicted Mean Vote 2 M Wm = Metabolic rate W 2 Wm I cl = Effective mechanical 1 clo power 0,155m² KW = Clothing insulation f cl t a t r v ar p a h c t cl = Clothing area factor = Air temperature, C = Mean radiant temperature, C 1 ms = Relative air velocity, P a 1 = Water vapour particle pressure, W m = Convective heat transfer coefficient, K 2 1 = Clothing surface temperature, C

7 PMV-index -3 Cold -2 Cool -1 Slightly cool 0 Neutral +1 Slightly warm +2 Warm +3 Hot GENERAL THERMAL COMFORT

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9 THERMAL COMFORT OPERATIVE TEMPERATURE -0,5 < PMV < +0,5 ; PPD < 10 % SPACES WITH MAINLY SEDENTARY OCCUPANTS : SUMMER CLOTHING 0,5 clo ACTIVITY LEVEL 1,2 met 23 C < t o < 26 C. Categories Category I II III IV Explanation High level of expectation and also recommended for spaces occupied by very sensitive and fragile persons with special requirements like some disabilities, sick, very young children and elderly persons, to increase accessibility. Normal level of expectation An acceptable, moderate level of expectation Low level of expectation. This category should only be accepted for a limited part of the year

10 Recommended categories for design of mechanical heated and cooled buildings Category Thermal state of the body as a whole PPD % Predicted Mean Vote I < < PMV < II < < PMV < III < < PMV < III < < PMV < Temperature ranges for hourly calculation of cooling and heating energy in three categories of indoor environment Type of building/ space Category Operative Temperature for Energy Calculations o C Offices and spaces with similar activity (single offices, open plan offices, conference rooms, auditorium, cafeteria, restaurants, class rooms, Sedentary activity ~1,2 met Heating (winter season), ~ 1,0 clo Cooling (summer season), ~ 0,5 clo I 21,0 23,0 23,5-25,5 II 20,0 24,0 23,0-26,0 III 19,0 25,0 22,0-27,0 IV 17,0 26,0 21,0-28,0

11 How to predict clothing insulation Chinese standard In the South colder indoor temperatures in winter (no heating) than in the north (heating allowed) Use the ISO7730 but allow -1 < PMV < + 1 For free running buildings apmv is introduced

12 Humidity limits according to ASHRAE Humidity limits according to ASHRAE

13 ADAPTATION Adaptation The above-mentioned requirements are based mainly on laboratory studies with test subjects mainly from Europe and North America. Studies with Asian and African subjects under laboratory test conditions have found similar results for general thermal comfort (Fanger, Tanabe, DeDear)

14 ADAPTATION The following text can be found in ASHRAE Handbook 1936, Chapter 3: It should be kept in mind that southern people, with their more sluggish heat production and lack of adaptability, will demand a comfort zone several degrees higher than those given here for the more active people of northern climates The RP-884 Global Database of Thermal Comfort Field Experiments

15 o ( C) FIELD STUDIES Adaptation 27 buildings with centralized HVAC 27 buildings with natural ventilation C) o 26 RP-884 adaptive model with semantics "PMV model RP-884 adaptive model "PMV model mean outdoor effective temperature ( o C) mean outdoor effective temperature ( o C) ADAPTATION IN NATURAL VENTILATED BUILDINGS? Behavioural Clothing, activity, posture Psychological Expectations

16 Daily mean clothing resistance for males and females in relation to outdoor temperature at 6 a.m. in HVAC buildings Clo mean male Clo mean female Linear (Clo mean female) Linear (Clo mean male) y = -0.01x R 2 = CLO y = x R 2 = Outdoor Temperature 6 a.m. [ C] Daily mean clothing resistance for males and females in relation to outdoor temperature at 6 a.m. in NV buildings 2.40 Clo mean male Clo mean female Linear (Clo mean female) Linear (Clo mean male) CLO y = x R 2 = y = x R 2 = Outdoor Temperature 6 a.m. [ C]

17 ASHRAE 55

18 ISO DIS Θ rm = (Θ ed ,8 Θ ed ,6 Θ ed ,5 Θ ed ,4 Θ ed ,3 Θ ed ,2 Θ ed -7 )/3,8 Natural ventilated buildingswithout mechanical cooling activity levels lie most of the time in the range of 1,2-1,6 met clothing insulation can be varied according to momentary preferences from 0,5 to 1,0 clo access to operable windows less than 4 persons per room such as dwellings and office buildings.

19 GENERAL THERMAL COMFORT AIR VELOCITY Preferred air velocity at increased temperature Direction of air velocity Large individual differences Personal control (fans, windows)

20 ASHRAE PERSONAL CONTROL Garment Description Sleeveless vest Thin sweater Light jacket Normal jacket Thermal Insulation clo 0,12 0,20 0,25 0,35 Change of Operative Temp. K 0,8 1,3 1,6 2,2

21 Relative importance of clothing 0,1 clo ~ 0,7 K LOCAL THERMAL DISCOMFORT FLOOR SURFACE TEMPERATURE VERTICAL AIR TEMPERATURE DIFFERENCE DRAUGHT RADIANT TEMPERATUR ASYMMETRI

22 DRAUGHT MEAN AIR VELOCITY TURBULENCE AIR TEMPERATURE DRAUGHT RATING, DR= (34-ta)(v-0.05)0.62(0.37 v Tu ) DRAUGHT

23 RADIANT TEMPERATURE ASYMMETRY VERTICAL AIR TEMPERATURE DIFFERENCE

24 FLOOR TEMPERATURE SEATED/STANDING PERSONS: 19 C < t s < 29 C BY HIGHER ACTIVITY LEVELS A LOWER FLOOR TEMPERATURE IS ACCEPTABLE CRITERIA FOR INDOOR AIR QUALITY ~VENTILATION RATES COMFORT (Perceived Air Quality) HEALTH PRODUCTIVITY ENERGY

25 Indoor Air Quality ASHRAE 62.1 acceptable indoor air quality: air in which there are no known contaminants at harmful concentrations as determined by cognizant authorities and with which a substantial majority (80% or more) of the people exposed do not express dissatisfaction. ASHRAE 62.1 General- Three different procedures are available to determine the outdoor airflow rates for mechanical ventilation systems. 1. Ventilation Rate Procedure- Prescribes rates & procedures based on typical space contaminant sources & source strengths 2. IAQ Procedure- Requires calculation of rates based on analysis of contaminate sources, concentration and perceived air quality targets 3. Natural Ventilation Rate Procedure- Proscribes design criteria for ventilation air to be provided through openings to the outdoors

26 Concept for calculation of design ventilation rate People Component Building Component Breathing Zone Outdoor Airflow V bz = R p P z + R s S d + R a A z Minimum l/s/person Number of People Ventilation per Smoker Number of Smokers Building Area Minimum l/s/m² CEN CR 1752 pren15251 ASHRAE 62.1 DIN 1946

27 Basic required ventilation rates for diluting emissions (bio effluents) from people for different categories Category Expected Percentage Dissatisfied Airflow per nonadapted person l/(s.pers) I II 20 7 III 30 4 IV 40 2,5* *The total ventilation rate must never be lower than 4 l/s per person ASHRAE Standard 62.1 : Adapted persons 2,5 l/s person (Cat. II ) Indoor pollution sources Human bioeffluents Building materials Furnishing HVAC system Equipment Tobacco smoking Building

28 Design ventilation rates for diluting emissions from buildings Category Very low polluting building l/(s m 2 ) Low polluting building l/(s m 2 ) I 0,5 1,0 2,0 II 0,35 0,7 1,4 III 0,2 0,4 0,8 IV 0,15 0,3 0,6 Non lowpolluting building l/(s m 2 ) Minimum total ventilation rate for health 4 l/s person 4 l/s person 4 l/s person ASHRAE 62.1

29 Example on how to define low and very low polluting buildings SOURCE Low emitting products for low polluted buildings Very low emitting products for very low polluted buildings Total VOCs TVOC (as in CEN/TS 16516) < μg/m³ < 300 μg/m³ Formaldehyde < 100 μg/m³ < 30 μg/m³ Any C1A or C1B classified carcinogenic VOC < 5 μg/m³ < 5 μg/m³ R value (as in CEN/TS16516) < 1.0 < 1.0 Total ventilation rate qtot n qp AR qb q supply = q tot / v Where v = the ventilation effectiveness (EN13779) q supply = ventilation rate supplied by the ventilation system q tot = total ventilation rate for the breathing zone, l/s n = design value for the number of the persons in the room, q p = ventilation rate for occupancy per person, l/s, pers A R = room floor area, m 2 q B = ventilation rate for emissions from building, l/s,m 2

30 Example of design ventilation air flow rates for a single-person office of 10 m 2 in a low polluting building (un-adapted person) Category Lowpolluting building l/(s*m 2 ) Airflow per nonadapted person l/(s*person) Total design ventilation air flow rate for the room l/s l/(s*person) l/(s* m 2 ) I 1, II 0, ,4 III 0, ,8 IV 0,3 2,5 5,5 5,5 0,55 Occupancy Category MINIMUM VENTILATION RATES IN BREATHING ZONE People Outdoor Air Rate R P Area Outdoor Air Rate R A Notes Occupant Density (see Note 4) Default Values Combined Outdoor Air Rate (see Note 5) cfm/person L/s person cfm/ft 2 L/s m 2 #/1000 ft 2 (#/100 m 2 ) cfm/person L/s person Correctional Cell Day room Guard stations Booking/waiting Educational Facilities Daycare (through age ) Classrooms (ages ) Classrooms (age Lecture l ) classroom Lecture hall (fixed Art t) classroom

31 Type of building/ space Single office (cellular office) Landscaped office Conference room Occupancy person/m 2 0,1 0,07 0,5 Category CEN Occupants only l/s person ASH- CEN RAE Rp Additional ventilation for building (add only one) l/s m 2 CEN lowpolluting building CEN Non-lowpolluting building ASH- RAE Ra Total l/s m 2 CEN Low Pol. A 10 1,0 2,0 2 B 2,5 7 0,7 1,4 0,3 1,4 C 4 0,4 0,8 A 10 1,0 2,0 1,7 B 2,5 7 0,7 1,4 0,3 1,2 C 4 0,4 0,8 A 10 1,0 2,0 6 B 2,5 7 0,7 1,4 0,3 4,2 C 1 l/s m 2 = 0.2 cfm/ft 2 4 0,4 0,8 0,8 0,7 2,4 ASH- RAE 0,55 0,48 1,55 CO2 as reference

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33 The design zone outdoor airflow (Voz) The outdoor airflow that must be provided to the zone by the supply air distribution system, shall be determined in accordance: Voz = Vbz/Ez Air Distribution Effectiveness V C C CEN Report CR 1752 (1998) E I C C S S Concentrations: C E exhaust air C S supply air C I breathing zone Mixing ventilation Mixing ventilation Displacement ventilation Personalized ventilation T supply - Vent. effect. T supply - Vent. effect. T supply - Vent. effect. T supply - Vent. effect. T inhal T inhal T inhal T room C - C - C - C - < 0 0,9-1,0 < -5 0,9 <0 1,2-1,4-6 1,2-2, , ,9-1, ,7-0,9-3 1,3-2, ,8 > 0 1 >2 0,2-0,7 0 1,6-3,5 > 5 0,4-0,7

34 Air Distribution Configuration Ceiling supply of cool air 1.0 Ceiling supply of warm air and floor return 1.0 Ceiling supply of warm air 15 F (8 C) or more above space temperature and ceiling return. Ceiling supply of warm air less than 15 F (8 C) above space temperature and ceiling return provided that the 150 fpm (0.8 m/s) supply air jet reaches to within 4.5 ft (1.4 m) of floor level. Note: For lower velocity supply air, Ez= 0.8. Floor supply of cool air and ceiling return provided that the 150 fpm (0.8 m/s) supply jet reaches 4.5 ft (1.4 m) or more above the floor. Note: Most underfloor air distribution systems comply with this proviso. Floor supply of cool air and ceiling return, provided lowvelocity displacement ventilation achieves unidirectional flow and thermal stratification Floor supply of warm air and floor return 1.0 Floor supply of warm air and ceiling return 0.7 Makeup supply drawn in on the opposite side of the room from the exhaust and/or return Makeup supply drawn in near to the exhaust and/or return location Ez ASHRAE 62.1 TABLE 6-2 Zone Air Distribution Effectiveness Adapted or Un-adapted? Bioeffluents (body odor) Adapted need only one third of outside air (7.7 l/s to 2.5 L/s) Tobacco smoke (ETS) Only limited adaptation (odor, irritation) Building materials and HVAC systems No adaptation

35 Adapted or Un-adapted? Conference rooms. Adapted? Classrooms. Adapted? Restaurants. Un-adapted? Department stores. Un-adapted HEALTH CRITERIA FOR VENTILATION Minimum 4 l/s/person

36 Indoor Air Quality Procedure The required ventilation rate is calculated as: G Q l/s Ci Co Ev where G = Total emission rate mg/s Ci = Concentration limit mg/l C o = Concentration in outside air mg/l E v = Ventilation effectiveness EPA Ambient-Air Quality Standards Contaminant Sulfur dioxide Particles (PM 10) Carbon monoxide Carbon monoxide Oxidants (ozone) Long Term Concentration Averaging μg/m 3 ppm b year 1 year Short Term Concentration Averaging μg/m 3 ppm 365 a 150 a 40,000 a 10,000 a 235 c 0.14 a 35 a 9 a 0.12 c 24 hours 24 hours 1hour 8 hours 1 hour Nitrogen dioxide Lead year 3 months d a Not to be exceeded more than once per year. b Arithmetic mean. c Standard is attained when expected number of days per calendar year with maxi-mal hourly average concentrations above 0.12 ppm (235 μg/m 3 ) is equal to or less than 1, as determined by Appendix H to subchapter C, 40 CFR 50. d Three-month period is a calendar quarter.

37 Pollutant Benzene WHO Indoor Air Quality guidelines 2010 No safe level can be determined WHO Air Quality guidelines Carbon monoxide 15 min. mean: 100 mg/m 3 1h mean: 35 mg/m 3 8h mean: 10 mg/m 3 24h mean: 7 mg/m 3 Formaldehyde 30 min. mean: 100 μg/m 3 - Naphthalene Annual mean: 10 μg/m 3 - Nitrogen dioxide Polyaromatic Hydrocarbons (e.g. Benzo Pyrene A B[a]P) Radon Trichlorethylene 1h mean: 200 μg/m 3 Annual mean: 40 mg/m 3 No safe level can be determined 100 Bq/m 3 (sometimes 300 mg/m 3, country-specific) No safe level can be determined WHO guidelines values for indoor and outdoor air pollutants Tetrachloroethylene Annual mean: 250 μg/m 3 Sulfure dioxide - 10 min. mean: 500 μg/m 3 24h mean: 20 mg/m 3 Ozone - 8h mean:100 μg/m 3 Particulate Matter PM 2,5 Particulate Matter PM h mean: 25 μg/m 3 Annual mean: 10 μg/m 3 24h mean: 50 μg/m 3 Annual mean: 20 μg/m 3 Residential buildings Cate gory Total ventilation including infiltration ( 1) air Supply air flow per. person (2) Supply air flow based on perceived IAQ for adapted persons (3) Supply air flow Bed room level (l/s) (4) Exhaust air flow, l/s peak or boost flow for high demand l/s,m 2 ach l/s*per q p l/s*per q B l/s,m 2 Master bed-room l/s l/s (3a) Other bedroom Kitchen Bathrooms (3b) Toilets (3c) I 0,49 0,7 10 3,5 0, II 0,42 0,6 7 2,5 0, III 0,35 0,5 4 1,5 0, IV* 0,23 0,4 5* 2,5*

38 Examples of lighting criteria for some buildings and spaces Ref. no. acc. to EN Type of area, task or activity Ē m lx UG R L U o R a Specific requirements Offices - Writing, typing, reading, data processing. Conference and meeting rooms ,60 80 DSE-work, see 4.9 Lighting should be controllable Educational buildings - Classrooms, tutorial rooms, Classroom for evening classes and adults education, Auditorium, lecture halls Educational premises Educational buildings - Sports halls, gymnasiums, swimming pools , ,60 80 Lighting should be controllable. See EN for training conditions. Daylight availability classification as a function of the daylight factor D Ca,j of the raw building carcass opening and D SNA Vertical Facades Daylight factor D Ca,j Roof lights Daylight factor D SNA Classification of daylight availability D Ca,j 6 % 7 % < D a SNA Strong 6 % > D Ca,j 4 % 7 % > D SNA 4 % Medium 4 % > D Ca,j 2 % 4 % > D SNA 2 % Low D Ca,j < 2 % 2 % > D SNA 0 % None a Values of D SNA > 10 % should be avoided due to danger of overheating

39 Building NOISE Type of space Equivalent Continuous Sound Level, Leq, nt,a [db(a)] I II III Residential Living room Bed room Places of assembly Auditoriums Libraries Cinemas Hospitals Bedrooms night-time Bedrooms daytime Hotels Hotel rooms (during night-time) Hotel rooms (during daytime) Offices Small offices Landscaped offices Restaurants Restaurants Schools Classrooms Teacher rooms Occupant Schedules

40 CONCLUSIONS THERMAL ENVIRONMENT Better agreement between ISO7730 and ASHRAE 55 Possibility for design at different levels of comfort Long term evaluation of thermal environment Issues being discussed Air velocity Humidity Adaptation in free running (natural ventilated) buildings CONCLUSIONS VENTILATION Both standards include an analytical method, where the required ventilation rate is calculated on the basis of comfort and health criteria. There is, however very little information on acceptable comfort and/or health criteria in the standards. There is a lack of information on emission rates from materials and other sources. This makes it very difficult today to use the analytical methods. Sources like people, activity, building, HVAC-systems and outdoor air must be taken into account. Influence of sources like people and smoking is available More information is needed on sources like buildings and HVAC systems. Relation between contaminant concentration and health effect is needed