Md. Code, Bus. Occ. & Prof. § 6.5-302

(a) A Grade 5 stationary engineer licensee may oversee the operation of a boiler that: (1) (i) can be operated at 30 to 99 horsepower; and (ii) is located in a building not open for public use; (2) is inspected in accordance with the boiler laws and regulations by a special inspector or a deputy boiler inspector; (3) if not equipped with a 24–hour computerized monitoring system and automatic controls, is visited by a Grade 5 licensee at least once every 24 hours that the boiler is in operation; and (4) if equipped with a 24–hour computerized monitoring system and automatic controls, is visited by a Grade 5 licensee at least once per week that the boiler is in operation, if the licensee: (i) is responsible for the safe operation of the equipment at all times; (ii) is available to observe the monitoring equipment or devices and make the necessary adjustments at least once every 24 hours; and (iii) maintains a daily inspection log. (b) A Grade 4 stationary engineer licensee may oversee the operation of a boiler that: (1) (i) can operate at 30 to 99 horsepower; and (ii) is located in a building open for public use; (2) is inspected in accordance with the boiler laws and regulations by a special inspector or a deputy boiler inspector; (3) if not equipped with a 24–hour computerized monitoring system and automatic controls, is attended by a Grade 4 licensee as follows: (i) at all times that the boiler is in operation; or (ii) if located in a school: 1. at all times during regular school hours; and 2. only when at least 150 students, faculty, or members of the public occupy the building where the boiler is located during nonregular school hours; (4) if equipped with a 24–hour computerized monitoring system and automatic controls, is attended by a Grade 4 licensee as follows: (i) if located in a hospital, hotel, residential facility, or other building generally open to the public, is visited at least once every 8 hours that the building is open for public use, if the licensee: 1. is responsible for the safe operation of such equipment at all times; 2. is available to observe the monitoring equipment or devices and make necessary adjustments at least once every 24 hours; and 3. maintains a daily inspection log; and (ii) if located in a school, is visited at least once every 8 hours: 1. during regular school hours; and 2. during nonregular school hours when the school building in which the boiler is located is occupied by at least 150 students, faculty, or members of the public, if the licensee: A. is responsible for the safe operation of such equipment at all times; B. is available to observe the monitoring equipment or devices and make necessary adjustments at least once every 24 hours; and C. maintains a daily inspection log. (c) A Grade 3 stationary engineer licensee may oversee the operation of a boiler that: (1) can operate at 100 to 299 horsepower; (2) is inspected in accordance with the boiler laws and regulations by a special inspector or a deputy boiler inspector; (3) if not equipped with a 24–hour computerized monitoring system and automatic controls, has a Grade 3 licensee in attendance at all times that the boiler is in operation; and (4) if equipped with a 24–hour computerized monitoring system and automatic controls, is attended by a Grade 3 licensee as follows: (i) if not located in a building open for public use, does not require regular full–time attendance or scheduled visitation, if the licensee: 1. is responsible for the safe operation of such equipment at all times; 2. is available to observe the monitoring equipment or devices and make necessary adjustments at least once every 24 hours; and 3. maintains a daily inspection log; and (ii) if located in a school, hospital, hotel, residential facility, or other building generally open to the public, is visited at least once every 8 hours that the building is open for public use, if the licensee: 1. is responsible for the safe operation of such equipment at all times; 2. is available to observe the monitoring equipment or devices and make necessary adjustments at least once every 24 hours; and 3. maintains a daily inspection log. (d) A Grade 2 stationary engineer licensee may oversee the operation of a boiler that: (1) can operate at 300 to 499 horsepower; (2) is inspected in accordance with the boiler laws and regulations by a special inspector or a deputy boiler inspector; (3) if not equipped with a 24–hour computerized monitoring system and automatic controls, has a Grade 2 licensee in attendance at all times that the boiler is in operation; and (4) if equipped with a 24–hour computerized monitoring system and automatic controls, is attended by a Grade 2 licensee as follows: (i) if not located in a building open for public use, does not require regular full–time attendance or scheduled visitation, if the licensee: 1. is responsible for the safe operation of such equipment at all times; 2. is available to observe the monitoring equipment or devices and make necessary adjustments at least once every 24 hours; and 3. maintains a daily inspection log; and (ii) if located in a school, hospital, hotel, residential facility, or other building generally open to the public, is visited at least once every 8 hours that the building is open for public use, if the licensee: 1. is responsible for the safe operation of such equipment at all times; 2. is available to observe the monitoring equipment or devices and make necessary adjustments at least once every 24 hours; and 3. maintains a daily inspection log. (e) A Grade 1 stationary engineer licensee may oversee the operation of a boiler that: (1) can operate at 500 or more horsepower; (2) is inspected in accordance with the boiler laws and regulations by a special inspector or a deputy boiler inspector; (3) if not equipped with a 24–hour computerized monitoring system and automatic controls, has a Grade 1 licensee in attendance at all times that the boiler is in operation; and (4) if equipped with a 24–hour computerized monitoring system and automatic controls and is attended by a Grade 1 licensee as follows: (i) if not located in a building open for public use, does not require regular visitation, if the licensee: 1. is responsible for the safe operation of such equipment at all times; 2. is available to observe the monitoring equipment or devices and make necessary adjustments at least once every 24 hours; and 3. maintains a daily inspection log; and (ii) if located in a school, hospital, hotel, residential facility, or other building generally open to the public, is visited at least once every 8 hours that the building is open for public use, if the licensee: 1. is responsible for the safe operation of such equipment at all times; 2. is available to observe the monitoring equipment or devices and make necessary adjustments at least once every 24 hours; and 3. maintains a daily inspection log.