Clarifying SCAQMD Rule 1403 and NESHAP

Asbestos compliance often comes down to how laboratory results are interpreted—especially when values are close to the 1% regulatory threshold. Misreading results can cause unnecessary remediation or, worse, missed hazards.

The Challenge: Point Counting Near 1%

Labs often use a method called point counting, which can show values just above or below 1% because of normal sampling variation. This creates confusion: does 1.05% or 1.35% require action?

The answer depends on how the law phrases the threshold. A key detail:

• NESHAP and SCAQMD use “greater than 1%”, not “greater than 1.0%.”
• This means results are rounded to the nearest whole number.

Practical Example

If point counting shows:

• 1.05% → rounds to 1% (not regulated)
• 1.07% → rounds to 1% (not regulated)
• 1.35% → rounds to 1% (not regulated)

Only results greater than 1% trigger Rule 1403 or NESHAP requirements.

Expert and Regulatory Confirmation

This clarification has been consistently taught by Armando Ducoing and his staff at Ecologics Training Institute and confirmed by Chris Ravenstein, SCAQMD Asbestos Program Supervisor. Both confirm that rounding down to the nearest whole number is fully compliant.

Why It Matters

• Overestimation → unnecessary abatement, costs, and delays.
• Underestimation → health risks and regulatory violations.
• Correct interpretation ensures both compliance and safety.

Staying Compliant

• Understand the threshold: “greater than 1%” is the rule.
• Communicate clearly with labs and regulators.
• Stay updated through trusted experts and agencies.

Conclusion

In asbestos management, small details make a big difference. Point counting results between 1.0% and 1.49% are rounded to 1%, and Rule 1403 does not apply. Knowing this distinction prevents costly errors and protects both workers and the public.

For further clarification, consult Ecologics Training Institute’s AHERA accredited training programs or your local air quality agency.