| #Q001 | monitoring | operational | recommended | Monitoring During Treatment Change | drinking water | Any change in treatment that will have a chemical, biological or physical impact on the distributed water should be carefully monitored in the distribution system. | During any change in treatment that will have a chemical, biological or physical impact on the distributed water | high |
| #Q002 | monitoring | health | recommended | Lead Levels Monitoring During Treatment Change | drinking water | Lead levels at the tap and within the distribution system should be closely monitored during a treatment change, especially a coagulant or disinfectant change. | During a treatment change, especially a coagulant or disinfectant change | high |
| #Q003 | administrative | health | recommended | Alternative Monitoring Protocol Adoption by Responsible Authorities | drinking water | Since elevated concentrations of lead can be found in drinking water as a result of leaching from plumbing materials, including fittings and fixtures, within a building, this protocol should be followed by responsible authorities, such as building owners or managers, school boards and employers, as part of the overall management of the health and safety of the occupants of schools, child care centres and other non-residential buildings. | Applicable to responsible authorities for non-residential buildings | high |
| #Q004 | administrative | health | guidance | Alternative Monitoring Protocol Adoption by Utilities | drinking water | This protocol may also be followed by utilities that want to include non-residential or residential buildings such as schools and multi-dwelling buildings in their corrosion control monitoring programs. | Utilities seeking to include non-residential or residential buildings in monitoring programs | high |
| #Q005 | monitoring | operational | recommended | Tier 1 Sampling Locations and Water Main Sample | drinking water | Tier 1 sampling should be conducted at the locations identified in the sampling plan for the non-residential/residential building. In addition, a sample that is representative of the water that is entering the building (water main sample) should be collected at each monitoring event. | During Tier 1 sampling events | high |
| #Q006 | monitoring | operational | recommended | Water Main Sample Collection Procedure | drinking water | Water main samples should be collected from a drinking water faucet in close proximity to the service line following a period of approximately 5 min of flushing (longer flushing may be necessary to ensure that the sample is representative of water that has been flowing in the main). | When collecting water main samples | high |
| #Q007 | prohibition | operational | recommended | Prohibition of Aerator Removal Prior to Sampling | drinking water | To ensure that representative samples are collected, the aerator or screen on the outlet should not be removed prior to sampling. | During collection of lead samples from outlets | high |
| #Q008 | monitoring | operational | recommended | Separation of Samples into Smaller Volumes | drinking water | It is recommended that samples be separated into smaller volumes (e.g., 2 x 125 mL). | When taking 250 mL Tier 1 or Tier 2 samples | high |
| #Q009 | corrective_action | health | recommended | Corrective Measures for Tier 1 Lead Exceedance | drinking water | If the lead concentration exceeds 0.005 mg/L (system goal) at any of the monitoring locations, it is recommended that the following measures be undertaken: 1. Educate the occupants... 2. Conduct additional sampling... 3. Implement interim corrective measures immediately... 4. Where a substantial amount of debris was removed from the aerator or screen, authorities may want to retest the water... | When Tier 1 lead concentration exceeds 0.005 mg/L | high |
| #Q010 | corrective_action | health | recommended | Immediate Corrective Measures for Tier 2 Lead Exceedance | drinking water | When the lead concentration in any of these second samples exceeds 0.005 mg/L (MAC), corrective measures should be undertaken immediately. Corrective measures can include interim measures, such as routine flushing of the outlet before the facility opens (a minimum of 5 min to obtain water from the water main), removing the outlet from service, using certified drinking water treatment devices or providing an alternative water supply, that are put in place until a permanent solution can be implemented. | When Tier 2 lead concentration exceeds 0.005 mg/L | high |
| #Q011 | corrective_action | health | recommended | Corrosion Control Measures Initiation based on Tier 1 and 2 | drinking water | In addition, depending on the results of the Tier 1 and Tier 2 sampling, one or a combination of the following corrosion control measures should be initiated: 1. Educate the occupants... 2. Compare the Tier 1 and Tier 2 sampling results... 3. Additional measures to consider... | Depending on the results of Tier 1 and Tier 2 sampling exceeding thresholds | high |
| #Q012 | monitoring | operational | recommended | First-Flush Sample Stagnation Time | drinking water | Therefore, first-flush samples should be collected following a minimum period of stagnation of 8 h, but not greater than 24 h, so that they are representative of the longer periods in which outlets are not used for drinking during most days of the week in a non-residential building. | Prior to taking first-flush samples in non-residential buildings | high |
| #Q013 | operational | health | recommended | Interpretation of Tier 1 and Tier 2 Sampling Results | drinking water | The results of Tier 1 and Tier 2 sampling should be interpreted in the context of the plumbing profile so that an assessment of the lead contributions can be made and the appropriate interim and long-term corrective measures can be taken. | Following the collection and analysis of Tier 1 and Tier 2 samples | high |
| #Q014 | monitoring | operational | recommended | General Building Sampling Compliance | drinking water | All other samples in the building should be collected using the protocol described below. | When conducting sampling in a building other than the water main sample | high |
| #Q015 | monitoring | operational | recommended | Simultaneous Sampling Confidence Warning | drinking water | In some cases, responsible authorities may want to collect Tier 1 and Tier 2 samples at the same time to eliminate the need to return to the site. In this case, authorities should be aware that the confidence in some sample results will decrease, since flushing water through one outlet may compromise the flushed samples taken from other outlets that are located in close proximity. | When collecting Tier 1 and Tier 2 samples simultaneously | high |
| #Q016 | monitoring | operational | guideline | Tier 1 Sample Collection Procedure | drinking water | A first-draw 250 mL sample is taken at the locations identified in the sampling plan after the water has been stagnant for a minimum of 8 h but generally not more than 24 h. | During Tier 1 sampling at non-residential and residential buildings | high |
| #Q017 | monitoring | operational | guideline | Tier 2 Sample Collection Procedure | drinking water | At those water fountains and cold drinking water outlets with lead concentrations that exceeded 0.005 mg/L for Tier 1, a second 250 mL flushed sample is taken after the water has been stagnant for a minimum of 8 h (but generally not more than 24 h) and then flushed for 30 s. | Follow-up sampling for outlets exceeding the Tier 1 system goal | high |