在设计和安装闭环地源热泵系统时，有必要了解适用的环境法规。在美国，近一半的州有规定或限制在地源热泵系统的地下回路中使用特定防冻剂或其他液体。其他一些州的法规尚未出台。虽然所有这些法规都是基于保护地下水和/或含水层质量的需要，但可接受的防冻剂清单因使用特定液体的国家而异。使用的典型防冻剂包括乙二醇、丙二醇、盐水、醇和醋酸钾。 每种方法都有其优缺点。所有州的法规状况都已确定。本文概述了这些法规，并概述了各州的担忧。单位:双引文:研讨会，ASHRAE交易，1998年，第104卷，pt。1A，旧金山

When designing and installing closed-loop ground-coupled heat pumps systems, it is necessary to be aware of applicable environmental regulations. Within the United States, nearly half of the states have regulations specifying or restricting the use of particular antifreezes or other fluids within the ground loop of a ground-coupled heat pump system. A number of other states have regulations pending. While all of these regulations are based on the need to preserve groundwater and/or aquifer quality, the list of acceptable antifreezes varies among those states with specified fluids. Typical antifreezes in use include ethylene glycol, propylene glycol, brines, alcohols, and potassium acetate. Each of these has its benefits and drawbacks. The status of the regulations has been determined for all of the states. An overview of the regulations is presented in this paper, along with a summary of the states' concerns.Units: Dual