followed by replacement), and "no scheduled maintenance". See also No Scheduled Maintenance and Break Down Maintenance Safety-Improvement Programs Practices intended to constantly improve safety within a plant or across a company, including, but not limited to, safety teams, safety awareness programs and communications, safety "days," safety training, and setting of continuous-improvement goals targeting safety metrics, such as OSHA reportable or lost-workday rates. Safety Instrumented Function (SIF) Safety Instrumented Function (SIF) is a safety function with a specified safety integrity level which is necessary to achieve functional safety. A Safety Instrumented Function can be either a safety instrumented protection function, or a safety instrumented control function. Safety Instrumented System (SIS) Safety Instrumented System (SIS) is a function to be implemented by a SIF, or other technology safety related system, or external risk reduction facilities, which is intended to achieve or maintain a safe state for the process, with respect to a specific hazardous event. The terms SIS and SIF are often used almost interchangeably. It should be noted, though, that a Safety Instrumented System is a combination of one or more Safety Instrumented Functions. Safety Integrity Level (SIL) The Safety Integrity Level (SIL) of a process is a measure of its safety, in terms of the extent to which a user may expect that process to perform safely, and in the case of failure to fail in a safe manner. SCADA Supervisory Control And Data Acquisition - SCADA system refers to the combination of telemetry and data acquisition. It consists of