12.

Pension and Employee Benefit Plans

We sponsor several non-contributory defined benefit pension plans for certain union employees. During 2013, the Company acquired two defined benefit pension plans covering eligible employees in the United States in connection with the acquisition of Met-Pro. All plans are funded in accordance with the funding requirements of the Employee Retirement Income Security Act of 1974.

We also sponsor a postretirement health care plan for office employees retired before January 1, 1990. The plan allowed retirees who attained the age of 65 to elect the type of coverage desired.

Retirement and health care plan expense is based on valuations performed by plan actuaries as of the beginning of each fiscal year. The components of the expense consisted of the following:


	Three Months Ended March 31, 2014			Three Months Ended March 31, 2013
Pension plan:
Service cost	$	50		$	17
Interest cost		357			78
Expected return on plan assets		(488	)		(102	)
Amortization of net actuarial loss		44			92

Net periodic benefit cost (gain)	$	(37	)	$	85


Health care plan:
Interest cost	$	1		$	1
Amortization of gain		(1	)		(4	)

Net periodic benefit gain	$	—		$	(3	)

We made contributions to our defined benefit plans during the three months ended March 31, 2014 and 2013 totaling $0.6 million and $21,000, respectively. We anticipate contributing $1.3 million to fund the pension plan and $21,000 for the retiree health care plan during the remainder of 2014. The unfunded liability of the plans of $6.5 million as of March 31, 2014 and December 31, 2013 is included in the Other Liabilities on our condensed consolidated balance sheets.