Correcting Low Airflow & Patient Comfort Issues in an Older Air Induction Unit

Our firm was recently contracted to provide TAB and outside air (OSA) verification for a 24-bed skilled nursing wing in a local hospital facility. This report was needed to provide re-certification, The Office of Statewide Health Planning & Development (OSHPD) Table 4A of the facility. The original design and build was completed November 18, 1971, and no major renovations had been completed other than normal maintenance.

The original 100 percent OSA air handler serving the secondfloor induction units was rated for 9,015 cubic feet per meter (CFM) at 7.5 in. static. When tested, we found the unit to be operating at 5400 CFM, 60 percent of the rated design, at 5.38 in. Each of the induction units had a design of 100

CFM to 105 CFM primary air. Once we performed a check of the induction units, we found that they were delivering less than half of the design airflow, and many had zero flow.

This project quickly became a survey to identify the issues, as it was clear that we would not be able to meet the required design for the system. After consulting with the facilities and the current mechanical engineer, a path was laid out to identify the major issues, and to determine what corrective action would be needed to achieve the results needed.

We continued with our survey and found numerous issues, such as system leakage due to old sealant that was broken and needed to be redone, clogged pre-filters in the induction units that had not been changed in six years based on the install dates written on the filters, and missing manual volume dampers. Further inspection of the induction units revealed that most had missing or broken balancing damper adjustment rods and dirty, clogged and/or worn out nozzles in the induction units.

Upon the completion of our survey and discussion with facilities personnel, we found it interesting that they proceeded to tell us about the ongoing issues they were having trying to maintain patient comfort – constant complaints of too hot/too cold – which was noted during the survey process.

A multi-step plan was discussed to correct and seal ductwork, replace the filters, clean the coils, clean the induction units, verify with carrier if the nozzles in the induction units need to be replaced, and to install and/or repair the missing and broken balancing dampers/adjustment rods. Once the corrective actions have been made, we will be returning to provide the original contacted TAB for the systems.

This type of system is rarely installed or used in medical facilities in our area, as the new OSHPD code requirements are much more difficult to maintain and meet. This system was also a learning experience for our younger technicians as they have not worked on an active induction unit system, but rather read about them in the AABC National Standards, and AABC Technician Training Manual. Developing a good relationship with the facilities personnel and mechanical engineer assisted our firm to move forward with this project, opened additional work, and provided new learning opportunities for our technicians.

Drinking Water Treatment Units Must Now Meet Stricter Requirements for NSF/ANSI Lead Reduction Certification

The joint committee governing the American National Standards for drinking water treatment units recently lowered the maximum allowable concentration of lead in treated drinking water to 5 parts per billion.

Standards 53 and 58 now require drinking water treatment units to reduce the lead in drinking water to 5 ppb or less — a 50% drop from the previous 10 ppb — and a threshold that matches Health Canada’s new maximum allowable concentration level of 5 ppb.

The new lead pass/fail criteria of 5 ppb has been published for NSF/ANSI 53: “Drinking Water Treatment Units - Health Effects” and NSF/ANSI 58: “Reverse Osmosis Drinking Water Treatment Systems.” Previously, a water treatment system could be certified if it reduced lead to 10 ppb or lower and met other requirements set by the standard, such as material safety and structural integrity. These other requirements remain unchanged.

Updates to both standards were published in December and are effective immediately for any new filter or filtration device claiming to reduce lead.

To be certified by NSF International, drinking water filters and treatment devices are tested with challenge water containing 150 ppb lead, 10 times the U.S. Environmental Protection agency’s action level of 15 ppb.

In March 2019, Health Canada lowered the national regulatory maximum allowable concentration of lead in drinking water from 10 ppb to 5 ppb. The European Union has also proposed a revision to its Drinking Water Directive to lower lead concentrations to 5 ppb.

The World Health Organization and other public health organizations have concluded there is no safe level of lead, and that even low concentrations can cause adverse health effects, especially for infants and children.

The primary source of lead in drinking water is from use of lead pipe or lead-containing alloys in supply lines and premise plumbing, fixtures, fittings, and solder. Given this widespread use, the cost of replacement and repair with non-lead contaminating materials can be cost prohibitive.

“Lead contamination of drinking water remains a critical issue, and regulations continue to be put into action to reduce the allowable level of lead in drinking water,” said Jessica Evans, director of standards development, NSF International. “Establishing this new pass/fail criteria of 5 ppb for NSF/ANSI 53 and NSF/ANSI 58 will further limit health risks associated with lead ingestion and provide an additional measure of public health protection.”

Residential water treatment industry products have demonstrated the ability to reduce lead concentrations to a level at or below 5 ppb when tested by NSF in accordance with standard protocols.

NSF/ANSI 53 and NSF/ANSI 58 and their updates are developed following the American National Standards Institute (ANSI) process designed to ensure openness, balance, consensus, and due process for all stakeholders. The Drinking Water Treatment Units Joint Committee is comprised of stakeholders representing consumers, the water industry, and state and federal health and environmental agencies in the U.S. and Canada. The joint committee includes 28 voting members and 80 observers who offer input and expertise during the standard development process and is facilitated by NSF International’s standards development group.

As the final step in the standards development process, the standard is ratified by NSF’s Council of Public Health Consultants, which includes representatives from the U.S. EPA, Health Canada and the U.S. Centers for Disease Control and Prevention (CDC). For more information, visit