| Lee Soo Hui Winson | 4444 | Access Platform Engineering | 2017-08-22 | WL Engineering Consultancy Pte. Ltd. |
| Lee Soo Hui Winson | 4444 | Amusement Ride Engineering | 2013-07-18 | WL Engineering Consultancy Pte. Ltd. |
| Lee Soo Hui Winson | 4444 | Crane Engineering | 2017-08-22 | WL Engineering Consultancy Pte. Ltd. |
| Lee Soo Hui Winson | 4444 | Lift and Escalator Engineering | 2017-08-22 | WL Engineering Consultancy Pte. Ltd. |
| Lee Yeong | 3899 | Geotechnical Engineering | 2007-04-19 | Landmark Consultant Pte. Ltd. |
| Leong Mun Tin | 3601 | Access Platform Engineering | 2017-05-22 | Gentech Engineering Pte Ltd |
| Leong Mun Tin | 3601 | Pressure Vessel Engineering | 2017-05-22 | Gentech Engineering Pte Ltd |
| Leong Mun Tin | 3601 | Lift and Escalator Engineering | 2017-05-22 | Gentech Engineering Pte Ltd |
| Leong Mun Tin | 3601 | Crane Engineering | 2017-05-22 | Gentech Engineering Pte Ltd |
| Leong Shee Kok | 2591 | Lift and Escalator Engineering | 2017-03-23 | SKL Engineering Services |
| Leong Siew Hay | 1475 | Lift and Escalator Engineering | 2018-04-11 | - |
| Leong Wai Hoo | 3901 | Crane Engineering | 2017-04-20 | United Engineering & Consultancy Services |
| Leong Wai Hoo | 3901 | Amusement Ride Engineering | 2011-02-17 | United Engineering & Consultancy Services |
| Leong Wai Hoo | 3901 | Lift and Escalator Engineering | 2017-04-20 | United Engineering & Consultancy Services |
| Leong Wai Hoo | 3901 | Access Platform Engineering | 2017-04-20 | United Engineering & Consultancy Services |
| Leong Weng Kwai | 2605 | Lift and Escalator Engineering | 2017-04-20 | - |
| Leong Yee Thye | 1778 | Pressure Vessel Engineering | 2017-08-22 | Harnical Engineering Pte Ltd |
| Leong Yee Thye | 1778 | Lift and Escalator Engineering | 2017-08-22 | Harnical Engineering Pte Ltd |
| Leong Yee Thye | 1778 | Access Platform Engineering | 2017-08-22 | Harnical Engineering Pte Ltd |
| Leong Yee Thye | 1778 | Crane Engineering | 2017-08-22 | Harnical Engineering Pte Ltd |
| Leung Chun Fai | 2748 | Geotechnical Engineering | 2006-05-16 | National University Of Singapore |
| Lew Geok Theng Michelle | 4366 | Geotechnical Engineering | 2012-07-17 | Kiso-Jiban Singapore Pte Ltd |
| Li Guojun | 4367 | Geotechnical Engineering | 2011-09-15 | Singapore Metro Consultant Pte. Ltd. |
| Li Kunlin | 4890 | Access Platform Engineering | 2017-06-15 | Thrive Engineering |
| Li Kunlin | 4890 | Lift and Escalator Engineering | 2022-01-27 | Thrive Engineering |
| Liam Kok Chye | 4057 | Crane Engineering | 2017-10-23 | Matcor Technology & Services Pte Ltd |
| Liew Jat Yuen Richard | 3749 | Protective Security Engineering | 2019-05-16 | National University Of Singapore |
| Liew Lee Lin @Theresa Liew | 3961 | Pressure Vessel Engineering | 2017-04-20 | IQS SERVICES PTE. LTD. |
| Liew Lee Lin @Theresa Liew | 3961 | Crane Engineering | 2017-04-20 | IQS SERVICES PTE. LTD. |
| Liew Lee Lin @Theresa Liew | 3961 | Lift and Escalator Engineering | 2017-04-20 | IQS SERVICES PTE. LTD. |