3S 是指民宿必須具有安全保障(Safety & Security)、衛生乾淨(Sanitation & Cleanness)、民宿精神(Spirits of host)，這也是3S 評鑑的目的。
3S民宿評鑑系統共有8個構面，70項指標。評鑑的8個構面包括整體外觀、消防安全、客房、浴室、餐食、環境衛生、資訊服務、民宿主人精神，所有住房客可能關心的項目，SGS都先檢查過了。通過這項評鑑的民宿才能獲頒SGS 3S 民宿標章與評鑑報告書作為識別。此識別也提供住房客選擇民宿的參考。
SGS 3S Home Stay Accommodations Assessment
The “3S Home Stay Accommodations Assessment” program, which is co-developed by SGS and Taiwan Rural Accommodation Association (TRAA), has been launched in 2012 through its physical assessment process around Taiwan.
3S means Safety & Security, Sanitation & Cleanness as well as Spirits of host, which are the main pillars of the assessment system and the focus of the assessment process.
The 3S Home Stay Accommodation assessment system includes 70 check points categorized into 8 major dimensions; namely Integrated appearance, Safety & Security, Guest room, Sanitary facilities, Food & Drink, Environment & Sanitation, Information & Communication and Spirits of Host. SGS provides an assessment program to accommodation facilities around Taiwan. All what visitors concerned areas are to be assessed by SGS following the defined assessment procedures. Once SGS passes the assessment, an SGS 3S Home Stay Accommodations recognition mark and its assessment report are issued to the assessed accommodations. In other words, the recognition mark as well as the assessment report is to give lodgers clear guideline for choosing the suitable place to stay.