The achievable flow rate is an important factor to consider when specifying an emergency shower. The ANSI/ISEA Z358.1-2014 which is the American standard that relates to emergency showers and eyewashes states that an emergency shower must be able achieve a minimum flow rate of 75.7 liters per minute for at least 15 minutes, the European standard (EN15154) is a similar specification: 60 lpm again for 15 minutes. These flow rates are necessary in order to deliver a sufficient volume of water in order to dilute any substances that can cause serious damage to the tissue of eyes and skin such as concentrated caustic soda for example.
Usually these high flow cannot be achieved from mains water sources alone, even in industrial settings. The water sources can also often be intermediate in many industrial environments making it difficult to guarantee the safety of employees using a mains fed tubular shower. A tank shower offers reliability in any environment, storing the required volume of water in an overhead tank and delivering the necessary flow rate using a dependable gravity fed system.