THE EFFECTS OF INDOOR ENVIRONMENT IN SUPERMARKET ON CLIENTS' AND OPERATORS' SATISFACTION

Transcription

1 THE EFFECTS OF INDOOR ENVIRONMENT IN SUPERMARKET ON CLIENTS' AND OPERATORS' SATISFACTION Wei l. Gu 1,2, Han Q. Wang 3, and Guang X. Kou 3 1 School of energy and power engineering, Central South University, Hunan, China 2 Department of urban construction, University of South China, Hunan, China 3 Zhuzhou Institute of Technology, Hunan, China ABSTRACT Supermarket is common in China because of its convenience and abundant merchandise. People in supermarket can be classified into two categories: clients and operators. This research measures the temperature and relative humidity of four supermarkets to describe the indoor thermal environment, investigates the satisfactory degree of clients and operators on the indoor environment, and analyses the reasons of dissatisfaction. KEYWORDS Supermarket, Indoor environment, Effects, Clients' and operators', Satisfaction INTRODUCTION Supermarket is common in China because of its convenience and abundant merchandise. Supermarket is kind of commercial building, but it still has own characteristics. Firstly, supermarket always locates at the first or second floor underground or ground, which causes natural ventilation; secondly, there has great number of people in supermarket and the time of people in supermarket is always long; thirdly, the merchandise in the supermarket are always open. All of these characteristics create the special indoor environment of supermarket. In modern life, people pay more attention on living quality. People pursue healthy shopping in stead of comfortable shopping in supermarket, and comfortable environment redounds to mentality health of people. Thus, this research is about the satisfactory degree of clients and operators on the indoor environment and the reasons of dissatisfaction. THE SCHEME OF INVESTIGATION AND MEASUREMENT Basic situation The aims of the research are four supermarkets (A, B, C, D) in Hengyang. Hengyang locates at Hunan province, central south of China. According to the architecture design criterion, Hengyang belongs to hot summer and cold winter zone. The basic weather data are shown in table1. Table 1 Basic weather data of Hengyang atmospheric pressure (kpa) mean daily temperature Summer outdoor weather data daily range dry-bulb temperature wet-bulb temperature wind speed m/s Corresponding Author: Tel: address: weiligu@sohu.com

2 atmospheric pressure (kpa) Winter outdoor weather data dry-bulb temperature relative humidity wind speed % 1.7m/s The four supermarkets locate at the central part of Hengyang. The mean area is about 22m 2, and the number of clients is large and steady. All of the supermarkets have two floors, A, B, C of them are on the ground, and D is underground. The four supermarkets all adopt all-air system. The fresh air requirement adopted is the minimum fresh air requirement recommended in the actual design criterion. The research includes investigation and measurement, which carry on at the same time. The duration of the research is 7 days from.1 to.7, 8:~12: am. Scheme of investigation The objects of investigation are clients and operators. The questionnaire used is international common and is modified based on the actual situation, such as whether the air environment can be accepted or not, and so on. The effect of vision environment and hearing environment on responders is considered. Besides, the selection of responders is based on the difference of age, sex. For operators, the effect of movement area is considered too. Scheme of measurement The measurement is adopted to describe the indoor thermal environment of supermarkets. The testing indexes indoor temperature and, the former is the main index to describe the indoor thermal environment, which is the main factor of the thermal comfort of body by affecting the sensible heat change of body through convection and radiation; the latter also affects the thermal comfort of body by affecting the evaporation on the skin surface. For temperature and relative humidity, the data used in analysis is the mean value of measure result. The vision environment and hearing environment are not measured quantificationally. RESEARCH RESULT AND ANALYSIS Result of measurement After 7 days measurement, the mean temperature variance and the mean relative humidity variance can be obtained, and the variance curves are shown in fig.1, fig.2. ( ) mean temperature oc indoor temperature in C supermarket 24 indoor temperature in D supermarket indoor temperature in A supermarket outdoor temperature indoor temperature in B supermarket ( ) relative humidity % in C supermarket in D supermarket in A supermarket in B supermarket outdoor relative humidity measurement duration measurement duration Figure 1 Curve of mean temperature variance Figure 2 Curve of relative humidity variance During the measurement, the weather changes, it rains in.4 and., so the relative humidity changes greatly; while rain not causes fall of temperature, the temperature is relatively steady. There are two

3 main reasons that cause the fluctuation of temperature and relative humidity. The first reason relates to the duration of measurement. The first day of measurement duration is May Day, the fourth day is weekend, and the seventh day is the last day of vacation. In the three days, the number of clients is very large. The heat gain and moisture gain from occupant of supermarkets is great, so the temperature in supermarkets rises without effective method of removing. The second reason relates to the operation of air-conditioning system in supermarkets. Hengyang belongs to small city; the automatic control lever of air-conditioning system is relatively low. There exists lag in the control of system, and the temperature and relative humidity in supermarkets can not be adjusted in time. In the four supermarkets, the D supermarket is underground with bad ventilation which has difficult in release of heat and moisture, so the temperature and relative humidity in D supermarket is higher than those of other three supermarkets. Result of investigation The result of investigation is the summary of the questionnaire. There are 728 responder in this investigation, in which are 476 clients and 2 operators. The distribution of responder in supermarkets is shown in table 2. Table2 Distribution of responder in supermarkets Number of clients Number of operators The investigation to clients carries out mainly at the exit and resting place of supermarkets. At this time, clients have finished shopping, and most of them stayed in supermarkets for about 1~1. hours. The investigation to operators carries out during 12:~12:. During this period, there are fewer clients in supermarkets, and the operators have enough time to finish the questionnaire. Till this time, most of operators have stayed in supermarkets for about 4hours. Besides, the subjective feeling of responders when they enter supermarkets is asked in the questionnaire for contrast. After analysis and comparison of the questionnaire, following results can be obtained: the largest ratio of dissatisfaction on thermal environment and air quality occurs in D supermarket; the largest ratio of dissatisfaction on vision environment and ear environment occurs in B supermarket. The detail are shown in figure 3 ~ figure 6. Along the x axis, there are the five degrees of subjective feeling, and the y axis is the percentage of different degrees of subjective feeling Figure 3 Ratio of satisfaction on the thermal environment

4 Figure 4 Ratio of satisfaction on the air quality Figure Ratio of satisfaction on the ear environment Figure 6 Ratio of satisfaction on the vision environment Among the four supermarkets, the largest ratio of dissatisfaction on thermal environment and air quality occurs in D supermarket, which relates to the architecture structure of D supermarket. Underground structure makes it difficult to ventilate, emit heat and moisture. Besides, the field of D supermarket is

5 rented, and the use of air-conditioning system needs additional charge. During the investigation in D supermarket, it is found that only part of the air-conditioning system works, and this causes higher mean temperature and asymmetrical distribution of temperature and relative humidity. The largest ratio of dissatisfaction on vision environment and ear environment occurs in B supermarket, which relates to the durative sales promotion and the use of great number of lamps. Synthesis analysis Measurement result shows that except the temperature and relative humidity of D supermarket are higher than the criterion, the temperature and relative humidity of other three supermarkets can satisfy the requirement of temperature and relative humidity determined in the design criterion. However, investigation result shows that the ratio of dissatisfaction of clients and operators is still high. The effect of clients characteristic in different period of time on the ratio of satisfaction about indoor environment The period of time is 8:~12:, investigation result shows in different period of time the client s characteristic is different. It is the beginning of a day s business in the period of 8:~9:. During this period, the old is the main part of clients. The reason is that in this period of time, supermarkets provide fresh vegetables. For most old people, purchasing vegetables is the job of a day. The result is that the number of people in unit time and space is great which causes indoor environment and high ratio of dissatisfaction. Investigation result shows that the ratio of dissatisfaction is 3.6% which exceeds the average level greatly. In other period of time, the client s characteristic has little effect on the ratio of dissatisfaction. The effect of clients and operators behavior characteristic on the ratio of satisfaction about indoor environment In supermarkets, the main behavior colonies are clients and operators. The different behavior characteristic causes the different recept of the same indoor environment. For clients, the mean time in the supermarket is under 1. hours which causes short adapting time to indoor environment. Investigation result shows that at the initial stage of clients in supermarkets, the ratio of dissatisfaction on air quality, vision and ear environment is great, about 4.3%, 42.1% and.6%, which relates to the environment different between door and outdoor supermarkets. At the final stage of clients in supermarkets, clients adapt the vision and ear environment gradually and the have lower ratio of dissatisfaction. While the ratio of dissatisfaction on indoor thermal environment raises, and the ratio of dissatisfaction on air quality has little change. For operators, the mean time in the supermarket is up to 8 hours which causes long adapting time to indoor environment. Besides, the movement area in supermarkets is different based on different position. Thus, compared to clients, at the beginning and final stage, the ratio of dissatisfaction on indoor environment of operators changes little, but higher than the ratio of dissatisfaction of clients. And the ratio of dissatisfaction of clients which have large movement area is lower than whom have small area. CONCLUSIONS From the analysis upwards, following conclusions can be obtained: (1) Among the four supermarkets, the order about indoor environment of supermarkets from to is C, A, B, D. (2) The ratio of dissatisfaction of clients and operators is still high even when the indoor temperature and humidity meet the requirement of design criterion, which indicates the indoor temperature and

6 humidity can not reflect the subject sense of clients and operators. Control of temperature, humidity and fresh air rate determined in the design criterion is not enough. (3) In controlling the indoor environment of supermarkets, proper control criteria and methods must be posed based on the personnel and behavior characteristic of clients and operators. REFERENCES 1. Sh. ZHANG and M. LIU (24) Impact of Thermal Environment on Subjective Acceptability of IAQ, Journal of Shandong University of Science and Technology (Natural Science), Vol. 23, L Fang, G Clausen and P O L Fanger ( 1997) Impact of Temperature and Humidity on Acceptability of Indoor Air Quality During Immediate and Long Whole body Exposure Proceedings of Healthy Buildings/ IAQ 3. ISO. International Standard 77 (1984) Moderate thermal environment determination of the PMV and PPD indices and specification of the conditions for thermal comfort. Geneva: International Standard Organization 4. XU Xiao lin and LI Bai zhan(2) Influence of Indoor Thermal Environment on Thermal Comfort of Human Body Journal of Chongqing University (Natural Science Edition), Vol. 28, Gen Clausen (1993) A comparative Study of Discomfort Caused by Indoor Air Pollution,Thermal Load and Noise,Indoor Air