guidance to amend or clarify portions of the final rule in 2013 .we anticipate that if the epa issues additional responses , amendments and/or policy guidance on the final rule , it will reduce the anticipated capital , operations and maintenance costs resulting from the regulation .generally , the nsps final rule will require expenditures for updated emissions controls , monitoring and record-keeping requirements at affected facilities in the crude-oil and natural gas industry .we do not expect these expenditures will have a material impact on our results of operations , financial position or cash flows .cercla - the federal comprehensive environmental response , compensation and liability act , also commonly known as superfund ( cercla ) , imposes strict , joint and several liability , without regard to fault or the legality of the original act , on certain classes of 201cpersons 201d ( defined under cercla ) that caused and/or contributed to the release of a hazardous substance into the environment .these persons include but are not limited to the owner or operator of a facility where the release occurred and/or companies that disposed or arranged for the disposal of the hazardous substances found at the facility .under cercla , these persons may be liable for the costs of cleaning up the hazardous substances released into the environment , damages to natural resources and the costs of certain health studies .neither we nor oneok partners expect our respective responsibilities under cercla , for this facility and any other , will have a material impact on our respective results of operations , financial position or cash flows .chemical site security - the united states department of homeland security released an interim rule in april 2007 that requires companies to provide reports on sites where certain chemicals , including many hydrocarbon products , are stored .we completed the homeland security assessments , and our facilities subsequently were assigned one of four risk-based tiers ranging from high ( tier 1 ) to low ( tier 4 ) risk , or not tiered at all due to low risk .to date , four of our facilities have been given a tier 4 rating .facilities receiving a tier 4 rating are required to complete site security plans and possible physical security enhancements .we do not expect the site security plans and possible security enhancements cost will have a material impact on our results of operations , financial position or cash flows .pipeline security - the united states department of homeland security 2019s transportation security administration and the dot have completed a review and inspection of our 201ccritical facilities 201d and identified no material security issues .also , the transportation security administration has released new pipeline security guidelines that include broader definitions for the determination of pipeline 201ccritical facilities . 201d we have reviewed our pipeline facilities according to the new guideline requirements , and there have been no material changes required to date .environmental footprint - our environmental and climate change strategy focuses on taking steps to minimize the impact of our operations on the environment .these strategies include : ( i ) developing and maintaining an accurate greenhouse gas emissions inventory according to current rules issued by the epa ; ( ii ) improving the efficiency of our various pipelines , natural gas processing facilities and natural gas liquids fractionation facilities ; ( iii ) following developing technologies for emission control and the capture of carbon dioxide to keep it from reaching the atmosphere ; and ( iv ) utilizing practices to reduce the loss of methane from our facilities .we participate in the epa 2019s natural gas star program to voluntarily reduce methane emissions .we continue to focus on maintaining low rates of lost-and-unaccounted-for natural gas through expanded implementation of best practices to limit the release of natural gas during pipeline and facility maintenance and operations .employees we employed 4859 people at january 31 , 2013 , including 705 people at kansas gas service who are subject to collective bargaining agreements .the following table sets forth our contracts with collective bargaining units at january 31 , 2013: .
[['union', 'employees', 'contract expires'], ['the united steelworkers', '406', 'october 28 2016'], ['international brotherhood of electrical workers ( ibew )', '299', 'june 30 2014']]
.

Question: what percentage of employees are subject to collective bargaining agreements?
Answer: 15%