Abstract: A screening system comprises a tank (20) containing a sewage screen (30), wherein the tank is configured for attachment to a sewage channel, and to receive sewage flow from an upstream point of the channel, and then to direct the sewage flow through the sewage screen (30), and then to return the screened sewage flow back into the channel, at a downstream point, or directly to a downstream treatment, and wherein the tank (20) is configured to decrease the velocity of the sewage flow in the tank relative to the channel, such that grit can settle at the bottom of the tank, and wherein the sewage screen (30) comprises a working screening surface (31), a portion of which lies in a substantially horizontal plane, and is positioned below the invert level of the sewage channel at the upstream point, when in use. Screen and tank used within the before mentioned system as well as the method of screening sewage using the system are also disclosed.

Abstract: Apparatus and a method are provided for detecting an abnormal rise in temperature associated with a combination of a cooking utensil (10) and a cooking zone (8) of a cooking surface (4) overlying an electric heater (6). The apparatus has a first temperature-responsive device (24) is provided within the heater and adapted to monitor temperature of the cooking surface (4). A second temperature-responsive device (26) is provided within the heater and adapted to monitor temperature of the cooking utensil (10) through the cooking surface (4) to provide an electrical output as a function of temperature of the cooking utensil. Means (28) is provided for calculating first and second derivatives (D1, D2) with time of the temperature sensed by the second temperature-responsive device (26) over an operating temperature range of the heater. Means (28) is provided to determine stabilization of the first derivative (D1) within stabilizing threshold limit values.