Silica dust limits: 2 California figures before you price

• Find the two California lines on the California Division of Occupational Safety and Health page: a 25 microgram action level and a 50 microgram permissible exposure limit, both as eight-hour time-weighted averages.
• Treat these figures as California's baseline, and confirm which state's rules apply to your job.
• Check whether your task is listed in Table 1 for your state before deciding whether an air test is needed.
• Write the chosen limit or Table 1 option on your quote sheet before adding dust control time to the price.

The California Division of Occupational Safety and Health states the action level for respirable crystalline silica is 25 micrograms in each cubic meter of air as an eight-hour time-weighted average. This figure appears on the page titled "Respirable Crystalline Silica Standards and Resources." The same publisher sets the permissible exposure limit for respirable crystalline silica at 50 micrograms in each cubic meter of air as an eight-hour time-weighted average. Both lines use the same unit and averaging period.

These two numbers are California's wording. The page does not describe them as rules for every state, every shop, or every job. When you price a cutting, grinding, or drilling job, treat these figures as the California baseline you must confirm for that specific work. Do not assume another state's page uses the same numbers unless that page says so. The action level and the exposure limit serve different roles in the standard, but both are defined by the eight-hour time-weighted average. For the wider site hazards, see Demolition safety: 9 rules to check on site .

Read the California page first because it names both limits in one place. The action level is the lower threshold, and the exposure limit is the higher threshold. Your quote sheet should record which limit applies to the task you are pricing. If the job involves respirable crystalline silica, write down the 25 microgram action level and the 50 microgram limit as the California figures. This step keeps the official language tied to the specific job you are bidding.

The California Division of Occupational Safety and Health defines the action level for respirable crystalline silica as 25 micrograms in each cubic meter of air, measured as an eight-hour time-weighted average California Division of Occupational Safety and Health . The same page states the permissible exposure limit for respirable crystalline silica is 50 micrograms in each cubic meter of air, also as an eight-hour time-weighted average California Division of Occupational Safety and Health .

The agency notes that employers performing high-exposure trigger tasks must comply with section 5204 even if exposures are below the action level California Division of Occupational Safety and Health . This requirement applies to the specific tasks identified as high-exposure triggers on that page. The 25 and 50 microgram lines are California's wording, not a universal standard for every state or shop. When pricing a cutting, grinding, or drilling job, you must verify which jurisdiction's rules apply to your specific work site.

Write the specific limit or table 1 choice that matches your job's location on your quote sheet. This step ensures you are applying the correct regulatory threshold before adding time or protection to the price. The California page provides the definitions for the action level and the permissible exposure limit, but your pricing decision depends on the local rules for your job site. Confirm the applicable limit for your specific jurisdiction before finalizing the bid.

The table below lists the two core dust limits for your pricing check, one in each row, using the definitions from the California Division of Occupational Safety and Health.

Each row restates one California line in plain words. The first row defines the action level, and the second row defines the permissible exposure limit for respirable crystalline silica. Keep these definitions separate when you price a job; do not mix a California limit with a Washington filter requirement. Write the specific line that matches your job on your quote sheet.

If your cutting task matches a specific entry in the official reference lists, you may skip the initial air sampling step. The California Division of Occupational Safety and Health states that construction employers who fully and properly implement the engineering controls, work practices, and respiratory protection listed in Table 1 of section 1532.3 for the specific equipment and tasks identified in that table do not have to separately measure employee exposures to confirm they are below the PEL California Division of Occupational Safety and Health . This exemption applies strictly when the controls are implemented fully and properly for the exact equipment and task named in the table.

Washington State Legislature rules define the scope for this alternative approach. The section applies to construction work and other occupational exposures where the task performed is indistinguishable from a construction task listed in Table 1 of this section and the task will not be performed regularly in the same environment and conditions Washington State Legislature . The key qualifier here is the irregularity of the task in that specific environment. If you perform the same cut repeatedly in the same shop conditions, the table alternative may not apply under this Washington rule.

Oregon Occupational Safety and Health describes Table 1 as a flexible alternative that identifies 18 common construction tasks that generate high exposures to respirable crystalline silica and specifies engineering controls, work practices, and respiratory protection for each task Oregon Occupational Safety and Health . The agency notes that this guide helps construction employers understand the methods listed in Table 1 for controlling exposures to silica dust. The count of 18 refers to the tasks listed in the state's table, not a count of tasks on your specific job site.

To use this path, verify that your specific cutting, grinding, or drilling task is listed in the table for your state. Confirm that the environment matches the conditions described, such as not being performed regularly in the same environment. If the task will be performed regularly in the same environment and conditions, the Washington table alternative does not apply, so assess the dust in the air. Write the specific table reference or the decision to sample on your quote sheet before adding protection time to the price.

The monitoring schedule on the California page is a compliance clock, not a line item on your quote sheet. Under California Code of Regulations, Title 8, Section 1532.3, if the most recent exposure monitoring shows employee exposures at or above the action level but at or below the permissible exposure limit (PEL), the employer must repeat that monitoring within six months of the most recent test ( California Division of Occupational Safety and Health ).

When the most recent non-initial monitoring indicates exposures below the action level, the rule requires repeating monitoring within six months of the most recent test until two consecutive measurements, taken seven or more days apart, are below the action level ( California Division of Occupational Safety and Health ). Once those two consecutive low readings are recorded, the employer may discontinue monitoring for the employees represented by that data, except where subsection (d)(2)(D) of the regulation provides otherwise. The number "2" in this rule refers to the count of consecutive measurements required to stop the cycle, not a duration or a frequency of work tasks.

Do not convert these regulatory intervals into a flat hourly add-on for dust control. The six-month monitoring cycle and the Washington medical surveillance trigger of 30 or more days a year are compliance obligations tied to exposure levels, not pricing inputs. Your bid should reflect the actual labor and equipment needed to keep exposures below these lines, not the regulatory timeline itself. If a job requires monitoring because exposures are near the action level, price the monitoring event as a distinct service line if you provide it, or note it as a client responsibility if they do. The regulatory clock tells you when to test; it does not tell you what the test costs.

Write the specific limit or Table 1 choice on your quote sheet before you finalize the price. The California Division of Occupational Safety and Health defines a High-efficiency Particulate Air (HEPA) Filter as a filter that is at least 99.97 percent efficient in removing mono-dispersed particles of 0.3 micrometers in diameter. If your job requires this specific filtration standard, record that definition on your sheet so the protection level is documented. Do not assume this definition applies to every state or every shop; it is the wording from this specific California page.

For jobs in Washington, check the task duration against the rules in WAC 296-840-110 . If an employee performs more than one task in Table 1 during a shift, and the total duration of all tasks combined is more than four hours, the required respiratory protection for each task is the respiratory protection specified for more than four hours in a shift. Write down whether your crew's combined tasks cross that four-hour threshold. This determines which protection level you must plan for, so mark that choice on your quote sheet.

The Washington State Department of Labor and Industries states that feasible engineering controls, like tools with vacuum attachments, are required if worker exposures to silica dust are over regulated limits. If your job involves cutting, grinding, or drilling that generates dust, note whether you are using tools with vacuum attachments. This is a documented requirement from the Washington page, not a suggestion. If you are not using these controls, you must confirm if your exposures are over the regulated limits.

A crew does 2 Table 1 tasks in one shift, totaling 5 hours. Because the combined time is more than 4 hours, the Washington rule requires the respiratory protection specified for more than four hours for each task. Price the higher protection level for both tasks, and record that choice on the quote sheet.

Open the California page, copy the 25 and 50 microgram lines onto your quote sheet, and only then adjust the price.

Related guides: Asbestos demolition: 3 amounts to check before pricing · Auto repair invoices: 7 checks before you bill a job · Check 9 job site material storage limits .

What is the difference between the action level and the exposure limit on the California page?

The action level is 25 micrograms in each cubic meter of air, and the permissible exposure limit is 50, both as eight-hour time-weighted averages California Division of Occupational Safety and Health . These two figures represent distinct regulatory thresholds within that specific state's standard.

Does table 1 replace an air test on every cutting job?

No. Only construction employers who fully and properly implement the engineering controls, work practices, and respiratory protection listed in Table 1 of section 1532.3, the California Division of Occupational Safety and Health notes they do not have to separately measure employee exposures to confirm they are below the PEL California Division of Occupational Safety and Health . This exemption applies specifically to the equipment and tasks identified in that table. It does not apply to every cutting job or every type of silica-generating task.

What does the ninety-five percent filter line apply to?

The Washington State Legislature specifies that intake air must be filtered through a filter that is ninety-five percent efficient in the 0.3-10.0 micrometers range Washington State Legislature . The page gives MERV-16 or better as an example of a filter meeting this efficiency standard. This requirement applies to the intake air filtration system described in the regulation.

When does the Washington page mention 30 days?

The Washington State Department of Labor and Industries states to offer medical surveillance for employees with exposures to silica over the action level 30 or more days a year Washington State Department of Labor and Industries . This duration threshold triggers the requirement for medical surveillance. It is a specific condition tied to the frequency of exposure over the action level.

Do these pages set a price for dust control?

These official pages define regulatory limits and control methods but do not set a dollar price for dust control, water, or labor. They provide the standards and requirements for compliance. Pricing for these controls remains a decision for the business owner based on their specific job costs. For water-related site checks, see Water safety: 9 checks for construction sites .