31 PROCEEDING OF INTERNATIONAL CONFERENCE ON MECHANICAL ENGINEERING RESEARCH AND APPLICATION 7 – 9 October 2020, Malang, Indonesia Determining the size of prayer mat based on the functional anthropometry for Javanese university students in Bangkalan Mahrus K. Umami * , Ilham Defriono, Imron Kuswandi Dept. of Industrial and Mechanical Engineering, Faculty of Engineering, Universitas Trunojoyo Madura Jl. Raya Telang, P.O. Box. 2, Kamal, Bangkalan, Indonesia *Email: mahrus.umami@trunojoyo.ac.id Abstract. Every Muslim individual has an obligation to pray five times a day. He/ she can do the ritual at a mosque, a prayer room, and some private areas. A place with a comfortable and an appropriate space would make individual performing the prayer well. Considering that most individual use a prayer mat during the ritual, this study aimed to identify an appropriate size of the prayer mat for Javanese students at the University of Trunojyo Madura (UTM) based on their functional anthropometry. Two hundred students (90 males) involved in the study. Seven postures of the prayers motions, namely: body height in standing posture (BHS), shoulder breadth (SB), foot length (FL), buttock to the top of the head in a bowing posture (BTHP), tip of foot finger to the top of the head (TFHP), elbow to elbow distance during prostrating (EEDP) and the maximum width during tawarruk sitting (the final sitting) (MWTS), were selected in the measurements phase. The postures performed by participants should conform to the right posture as exemplified by the Prophet Muhammad. Results of the current study indicate a significant difference in the included dimensions between the male and female groups, except on the maximum width during the tawarruk sitting. This finding implies to the different size on the prayer mat, especially on its length. It also indicates the need of different space between the lines during a congregational prayer. Keywords: prayer mat, functional anthropometry, congregational prayer 1. Introduction Muslim prayer is an Islamic ritual, consists of a series of intention, recitations, and motions, started by a "Takbiratul ihram" and finished by a "Salam" [1,2]. The procedure for performing prayer is arranged according to the guidance of the Prophet Mohammad. There is no one allowed to add or eliminate even a motion in his/her prayer, except it was shown by exemplified by the Prophet previously [2,3]. There are four main postures performed by the Muslims in his/her prayer, namely: standing, bowing, and prostrating. These postures are mandatories for healthy individuals without any disability [4]. For individuals who are sick or unable to perform these postures, there are some reliefs so that they can pray according to his/her ability. For example, they can pray in a sitting, laying on side, or laying on back posture [2,3]. Five times prayers are obligatory for all Muslims [1-3]. To implement the obligation, Muslim individuals usually go to pray at a specific prayer place, e.g. a mosque or a prayer room. It is also possible for Muslim individuals to do the ritual at a private area such as home, office room, and other places. The Muslim people normally use a prayer mat when they do the ritual at a private area or at a mosque [5]. The main function of a prayer mat is to provide a clean area for praying. The availability of the clean area is crucial since it is a must. The ritual would not be acceptable if the area is not clean [1]. The prayer mat varies in its size, material, accessory, etc. The variances occur since there is no standard specification of the prayer mat. It is easy to find a few different sizes of prayer mat for