There are several types of FMEA and they should always be done whenever failures would mean potential harm or injury to the user of the end item being designed. But, the most known and used types of FMEA are:
DFMEA vs PFMEA
The DFMEA focuses on components and subsystems. The primary objective of a Design FMEA is to uncover potential failures associated with the product that could cause product malfunctions, shortened product life and/or safety hazards while using the product.
Figure 2: DFMEA Example
On the other hand, the PFMEA focuses on manufacturing and assembly processes. The Process FMEA uncovers potential failures that can impact the product quality, reduce the process reliability, cause customer dissatisfaction and create safety or environmental hazards.
The objectives of PFMEA are to maximize system quality, reliability, and productivity, and minimize production process, based on failure effects in the system. So, the main difference between DFMEA and PFMEA are the each one focus. Below there is an example of PFMEA:
Figure 3: PFMEA Example
It is up to you: For each situation, choose the best type of FMEA.