Name

1.	Question text:
	CO sensor


2.	Design summary:
	Very well written. Low Battery detection / alert is especially well done 

3.	Block diagram
	Where is the block diagram?
	you have given the entire electrical circuit diagram here.
	Only some logical / hierarchical block diagram was needed here.
	
4.	Power supply design
	There are two major probems with your design.
	a. The 9V battery you have chosen is not exactly good for long life. Look at other products that need long life batteries -
	all use some kind of non-rechargeable lithium cells.
	b. You are using a linear regulator which has expremely poor efficiency - you're going from 9V to 5V!
	Should have used a 6V battery and LDO.
	Microcontroller - pick one with low power consumption and/or sleep modes like the MSP430 or AtTiny.

5.	Industrial Design:
	Summary is fine - should have included sketches of the final unit. Where should the LED be? Where are the mountings for
	buzzer / speaker? 

6.	KICAD Design
	Schematic:
	No major issues seen
	
	PCB:
	Layout could be a little better - you have many traces intersecting / overlapping.
	Especially look at the sensor heater supply - those traces could be thicker.
	What is the current needed there?
	
7.	Pricing / BOM / Assembly
	Some BOM optimisation could have been done - mostly all ok
	Price for 2 prototypes not mentiones?