Yesterday I got a call back from a rep at Royal Oak. Again, I related the question of the Premium briquet content to the Ultra 100 listed content of 100% hardwood charcoal. The rep said that basically ALL their briquets were the same (hmm, that's interesting). By email, she sent me the MSDS for Royal Oak charcoal. Here are some relevant extracts with a few comments:
TRADE NAME: Charcoal Briquets
BRAND NAMES: Royal Oak, Great Lakes, Grill Time, Nature-Glo, Ole Diz and private labels.
(Note: that the instant lite and Ultra 100 are not included explicitly in the list.)
DATE: 09/12/2011 SUPERSEDES DATE: 01/02/2009
MANUFACTURER: ROYAL OAK ENTERPRISES, LLC.
(Note: the date of this MSDS superseded an earlier one -- is this because these are the "new" briquets?)
Composition:
Char dust 75-80%
Limestone < 15%
Sawdust < 10%
POTENTIAL HEALTH EFFECTS:
INHALATION: Overexposure to the dust from briquet breakage may cause transitory upper respiratory irritation.
CARCINOGENICITY: Not listed by NTP or IARC. Not regulated as a carcinogen by OSHA.
(Note: I don't think any of us would argue that we don't want to breathe charcoal dust.)
DECOMPOSITION PRODUCTS: Product will burn and the products of complete combustion are oxides of carbon.
CALIFORNIA PROPOSITION 65: Not regulated under California Proposition 65.
So putting this all together, this is what I understand. Limestone (cement) and wood dust is mixed with hardwood charcoal dust (presumably with a little water) to make the formed briquets when dried. The limestone and sawdust are a binder which is less than 25% of the entire content which accounts for it having LESS ash than Kingsford but more ash than those that use 5% vegetable binder (Stubbs and Rancher/Trader Joe's). On heating, the binder breaks down (being calcium carbonate and wood dust) which leaves a less solid partially burned coal than the vegetable binder (which may be because that "cooks"?).
Anyway, I don't know of anything in these ingredients that suggest a problem and they don't smell bad when burned -- just not as "woody" as lump charcoal.
So I'm good with using "new" Royal Oak briquets. I'd also like to find the Ultra 100 version. And now I'll get on with the "testing" I promised -- but probably not until after Thanksgiving. Too much happening in our household right now.
Rich