California Home	ARB:	Home	Search	Site Map				Contact Us

	Annual Statewide Toxics Summary Silicon FAQs nanograms per cubic meter

Year	Months Present	Minimum	Median	Mean	90th Percentile	Maximum	Standard Deviation	Number of Observations	Detection Limit
2017		*	*	*	*	*	*	0	*
2016		*	*	*	*	*	*	0	*
2015		*	*	*	*	*	*	0	*
2014		*	*	*	*	*	*	0	*
2013		*	*	*	*	*	*	0	*
2012		*	*	*	*	*	*	0	*
2011		*	*	*	*	*	*	0	*
2010		*	*	*	*	*	*	0	*
2009		*	*	*	*	*	*	0	*
2008		*	*	*	*	*	*	0	*
2007		*	*	*	*	*	*	0	*
2006		*	*	*	*	*	*	0	*
2005		*	*	*	*	*	*	0	*
2004		*	*	*	*	*	*	0	*
2003		480	2400	*	5600	17000	2980	86	2
2002		92	4200	5240	11000	23000	3900	491	2
2001		130	3500	4550	9800	19000	3620	505	3
2000		94	3800	4650	10000	23000	3770	472	3
1999		130	3300	4630	9900	27000	4080	565	3
1998		42	2600	3680	8300	28000	3670	559	3
1997		85	3200	4110	8100	27000	3760	553	3
1996		74	2800	3770	8400	21000	3390	595	3
1995		53	3400	4390	9900	24000	4130	602	3
1994		90	3300	4060	8600	17000	3130	585	3
1993		91	3500	4350	9200	24000	3850	575	3
1992		44	3500	4540	9700	40000	3940	554	3
1991		100	4000	5520	12000	62000	5150	567	3
1990		400	5900	*	15000	28000	5180	309	3
1989		*	*	*	*	*	*	0	*

	Notes:	Values below the Limit of Detection (LoD) assumed to be ½ LoD. Means and risks shown only for years with data in all 12 months. "*" means there was insufficient or no data available to determine the value.