Frequently Asked Questions
Q: Does John V. Dinan Associates have seismographs for sale?
A: No, John V. Dinan Associates does not provide instruments for sale.
Q: Does John V. Dinan Associates have vibration monitoring instrumentation for rent?
A: As an alternative or supplement to the manually operated seismograph, John V. Dinan Associates can provide automatic units, which can be installed on a long-term basis. When installed this seismograph shall continuously monitor construction vibration in an adjacent building or other secure location. Our service also includes a weekly visit to download and analyze the date, prepare a weekly report based on the data collected, and consultation related to the review and/or analysis of data. We provide these services for a weekly or monthly fee.
Q: Are telltales used to monitor horizontal and vertical movements?
A: A telltale also known as a crack monitor is a basic joint movement indicator. This device can help determine if any pre-existing crack is dynamic or static. The monitor is a small devise approximately 1.5 inched tall by 7 inches wide. The monitor measures horizontal and vertical movement across a crack on a flat surface to an accuracy of +/- 1.0mm and by interpretation to +/- 0.5mm. The telltale monitor is not used to measure vertical and horizontal movements pertaining to walls or structures. This scope of work would be conducted by a surveyor.
Q: Does John V. Dinan Associates perform pre construction surveys and/or vibration monitoring within NYCTA (New York City Transit Authority) structures?
A: Yes, John V. Dinan Associates is approved to conduct all NYCTA, MTA, NJT, & LIRR work. We have all of the appropriate insurance and have been working with these organizations since 1925.
Q: How long does it take to complete a pre construction survey?
A: Every project is unique and requires a logistical approach; therefore the timeline varies accordingly with each individual project. We would be happy to discuss your specific project with you and go over any special needs the project may have.
Q: Does John V. Dinan Associates provide any geotechnical or surveying services?
A: Yes, John V. Dinan Associates provides geotechnical and/or surveying services as an integral part of each projects' scope of work.
Q: Is it possible to receive a copy of a pre construction survey report that was previously completed?
A: John V. Dinan Associates shall provide additional copies of the reports to the original client for an additional fee. If an adjacent property owner or other entity would like a copy of a report, they would need to go through the client to get a copy or have the client contact us to authorize the issuance of any additional reports.
Q: Does the pre-construction survey contain a structural evaluation of the existing condition?
A: All items addressed in our report shall only pertain to the visible construction components of the building. Any items falling within the scope of the structural system, electrical systems amd mechanical system including heating, air conditioning and elevators (other than a visual condition description) shall not be addressed in our report.
Q: Does John V. Dinan Associates offer services for projects located in historic districts or on historic landmarked structures?
A: Yes, John V. Dinan associates has performed hundreds of pre construction surveys on historic landmark structures as well as on structures within historic districts. We make sure to follow the guidelines outlined in the TPPN: 10/88. We also create vibration monitoring plans, landmark protection plans, and roof protection plans, which may be required for projects within a landmark district or individual landmark structures.
Q: What is the difference between manual and automatic vibration monitoring?
A: Vibration monitoring is when we sent a seismologist to the job with a vibration monitor (or multiple monitors if needed) and the seismologist will analyze the data from the vibration monitoring machine during the course of construction each day. He is available to tell you instantly if a vibration reading is too high or to go over data with you daily. The seismologist is also able to move the monitor(s) to multiple locations around the site. Automatic vibration monitoring is when an automatic monitor, which runs 24 hours a day, is placed in a secure location with a power source (usually a basement). The automatic vibration monitoring includes necessary visits to install and remove our equipment, a brief weekly visit to remove the records obtained for analysis and interpretation, a weekly report, and a normal amount of consultation related to the review and/or analysis of data.
Q: Does John V. Dinan Associates provide sirens and strobe lights for automatic vibration monitoring?
A: Yes, John. V. Dinan has both sirens and strobe lights, which can be installed with the automatic seismographs, when applicable, depending on the project specifications.
Q: Where are the seismograph instruments typically placed for automatic vibration monitoring?
A: When automatic vibration monitors are required for a project they are placed in the lowest level of the adjacent structure/s (usually a cellar or sub cellar) along the wall within closest proximity to the construction activities.
