A safety consultant asked OSHA six questions about the respirable crystalline silica (RCS) standard for construction, starting with what makes a water delivery system 'integrated' for Table 1 purposes. OSHA answered that the system must be designed, developed, and supplied by the manufacturer specifically for the tool in use, must connect directly to the tool, and must be operated and maintained in accordance with the manufacturer's instructions related to minimizing dust emissions. Manufacturer-designed systems are required because they are more likely to control dust effectively by applying water at the right emission points. A system rigged up by the employer, or an independent water sprayer operated by a second employee, does not meet Table 1 — though such controls may still comply under paragraph (d).
If controls don't meet Table 1 criteria, exposure assessments are required. Employers must either fully implement Table 1's specified engineering controls, work practices, and respiratory protection, or assess and limit employee exposure in accordance with paragraph (d), including exposure assessments and compliance with the permissible exposure limit (29 CFR 1926.1153(d)).
On the 5-day employee notification clock: under the performance option, the assessment is complete when the employer has characterized the employee's 8-hour TWA exposure based on air monitoring data, objective data, or both. Under the scheduled monitoring option, the clock starts when results are received — from the consultant if a third party is used, or from the laboratory for internal assessments. OSHA stressed that the standard does not give employers extra time to study results, meet with employees, run quality assurance checks, or draft a formal report before notifying.
On medical surveillance: it's triggered only when an employee will be required under the RCS standard itself to use a respirator 30 or more days per year (29 CFR 1926.1153(h)(1)(i)). Respirator use required only by employer policy doesn't count toward the 30 days — though the respiratory protection standard (29 CFR 1910.134) still applies to any respirator use. Any required use during a day, even 10 minutes, counts as one day, and a 14-hour shift still counts as a single day. Eligibility is based on the employer's reasonable estimate of expected respirator days over the coming twelve months.