important:

WISHA currently uses the IDLH values in the 1990 NIOSH Pocket Guide to Chemical Hazards to determine the existence of IDLH conditions. The employer may use more recent editions of this guide. Visit https://www.cdc.gov/niosh for more information.

(1) The employer must provide at least two standby employees outside the IDLH area.

Note:	The employer need only one standby employee if the IDLH condition is well characterized, will remain stable AND the employer can show one employee can adequately do ALL of the following:
	1. Monitor employees in the IDLH area;
	2. Implement communication;
	3. Initiate rescue duties.

(2) The employer must train and equip standby employees to provide effective emergency rescue. Equip them with:

(a) A pressure-demand SCBA or a pressure-demand air-line respirator with an auxiliary SCBA, for each standby employee;

(b) Appropriate retrieval equipment, when it would help with the effective rescue of the entrant, or an equivalent means of rescue.

(3) The employer must make sure standby employees maintain visual, voice, or signal line communication with employees in the IDLH area;

(4) The employer must make sure that in the event of an emergency:

(a) Standby employees notify the employer or the employer's designee before they enter the IDLH area to provide emergency rescue;

(b) The employer provides necessary assistance when notified.

PDFWAC 296-307-61405

Provide standby assistance in immediately dangerous to life or health (IDLH) conditions.