Property, plant and equipment (Tables)

3 Months Ended

Mar. 31, 2024

Property, plant and equipment

Schedule of elements of property, plant and equipment

	March 31,		December 31,		Estimated
	2024		2023		Lives
(in thousands)	(unaudited)
Property, plant and equipment
- Land	$	1,255	$	1,255
- Land improvements		319		319	6-10 years
- Buildings		1,446		1,446	25-39 years
- Building improvements		3,467		3,467	25-39 years
- Cylinders		13,220		13,220	15-30 years
- Equipment		29,759		29,397	3-10 years
- Equipment under capital lease		315		315	5-7 years
- Vehicles		1,790		1,790	3-5 years
- Lab and computer equipment, software		3,233		3,233	2-8 years
- Furniture & fixtures		1,124		933	5-10 years
- Leasehold improvements		865		865	3-5 years
- Construction-in-progress		3,127		2,844
Subtotal		59,920		59,084
Less: Accumulated depreciation		(40,453)		(39,709)
Total	$	19,467	$	19,375