Section 5-602 - Work in confined spaces(a)(1) In this section the following words have the meanings indicated.(2) "Confined space" means a space that, by design: (i) has limited openings for entry and exit; and(ii) is subject to: 1. the accumulation of a combustible agent;2. an accumulation of a toxic agent; or3. a deficiency of oxygen.(3) "Confined space" includes: (ix) a tank that is enclosed or has an open top;(xiii) a process vessel; or(4) "Maintenance work" means cleaning, inspection, maintenance, painting, repair, servicing, or other similar work.(b) A person described in § 5-101(d)(2)(ii) or (iii) of this title may not allow or cause an individual described in § 5-101(c)(2)(iii) or (iv) of this title to do maintenance work in a confined space, unless the Commissioner:(1) grants written authorization based on a satisfactory showing that work practices in effect will protect the health and safety of the individual; or(2) in accordance with Subtitle 3 of this title, passes an order for a variance.(c)(1) This subsection applies only to an employer who is a subcontractor.(2) Each subcontractor who, under an original contract or subcontract, is to do maintenance work in a confined space shall give the Commissioner: (i) at the commencement of the maintenance work, oral notice of the maintenance work to be performed; and(ii) within 24 hours after the oral notice, written notice of the maintenance work.