of the land to build the plant. Safety concerns: consideration towards risk analysis on industrial accidents or hazardous chemicals. Environmental impact and projected effluents and emissions Waste production/recycling: manage waste produced as side product of the process for not to harm the surroundings. Operating and maintenance costs: represent the variable cost of the operational of the plant. Other factors that designers may include are: Reliability Redundancy Flexibility Anticipated variability in feed stock and allowable variability in product. Sources of design information Designers usually do not start from scratch, especially for complex projects. Often the engineers have pilot plant data available or data from full-scale operating facilities. Other sources of information include proprietary design criteria provided by process licensors, published scientific data, laboratory experiments, and suppliers of feedstocks and utilities. Design process Design starts with process synthesis - the choice of technology and combinations of industrial units to achieve goals. More detailed design proceeds as other engineers and stakeholders sign off on each stage: conceptual to detailed design. Simulation software is often used by design engineers. Simulations can identify weaknesses in designs and allow engineers to choose better alternatives. However, engineers still rely on heuristics, intuition, and experience when designing a process. Human creativity is an element in complex designs. See also Chemical engineer Chemical plant Chemical process Process integration Process simulation Chemical process modeling Environmental engineering Industrial process List of chemical process simulators Process engineering Process safety Unit process Recommended chemical engineering books References External links Chemical Process Design Open Textbook (Northwestern University by Fengqi You) A General Framework for Process Synthesis, Integration, and Intensification (OSTI / Texas A&M University) Process engineering